8 arrested over deadly Esparto explosion. How did events unfold?
An expansive criminal investigation of the July 1 Esparto explosion has led to the arrests of seven men and one woman.
Investigators Friday outlined the indictments against the eight arrested, including murder charges against five of those arrested. Seven died in the deadly blast.
In the 283 days between the explosion and the culminating arrests made on April 9, several revelations have been made about the loopholes in the licensing process and a sprawling fireworks’ operation.
To help you understand the context and chronology, we have crafted a timeline.
In some cases, we cite the month and year the events occurred. When possible, we cite the specific dates.
Timeline before and after the explosion
2022: Yolo County building officials flagged the need for additional precautionary measures before approving a new metal warehouse at the property on County Roads 23 and 86A in 2022. Curtis Lawrence, Esparto Fire Protection District chief, assured county staff the property was safe, according to a trove of emails and other documents. His department never conducted formal inspections.
May 21, 2025: Cal Fire’s Office of the State Fire Marshal and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives agents seized more than 100,000 pounds of illegal fireworks at a warehouse in the Los Angeles suburb of Commerce. Some of those fireworks belonged to Kenneth Chee, owner of Devastating Pyrotechnics.
May 23, 2025: The Los Angeles County Fire Department’s arson unit inspected the warehouse. An official report noted the presence of display fireworks, the type used for municipal fireworks shows, citing an “unpermitted high pile storage of hazardous materials.”
July 1, 2025: A large explosion rocked the town of Esparto when a firehouse facility in a warehouse located at 26400 block of Country Road 23 near Country Road 86A, about a mile south of Highway 16. The blast led to a 78-acre blaze. Seven people were missing and later determined to have been killed in the blast.
July 2, 2025: Volunteer firefighter and owner of BlackStar Fireworks Craig Cutright, sent a text message to Fire Chief Curtis Lawrence which lead to a face-to-face meeting
July 2, 2025: Esparto fire officials said they were aware the storage facility contained commercial fireworks. A report that details special assessments by the Esparto Fire Protection District, obtained by The Sacramento Bee, shows officials charged the facility just $456 for a special safety assessment, far less than the fees paid by a local taqueria or a small supermarket. The fire district’s report on special assessments cited a hypothetical example of a high-risk operation: “a fireworks factory.”
July 4, 2025: Craig Cutright resigns from BlackStar Fireworks amid an investigation into the blasts tied to the two improperly licensed fireworks operations.
July 8, 2025: Personnel from the San Francisco Police Department alongside a bomb squad from sheriff’s offices from Sacramento and Yolo counties search a home registered to Jack Lee, who Devastating Fireworks’ operations manager, in San Francisco.
July 9, 2025: Family members identified their lost loved ones: Jesús Ramos, 18; Jhony Ramos, 22; Joel “Junior” Melendez, 28; Carlos Rodriguez-Mora, 43; Angel Mathew Voller, 18; Christopher Bocog, 45; and Neil Li, 41.
July 16, 2025: Public records from the Esparto Fire Protection District show that Chief Curtis Lawrence knew more than he’d previously disclosed about Devastating Pyrotechnics.
July 23, 2025: A growing body of public records and interviews show how the company and its associates repeatedly presented themselves as fireworks manufacturers despite lacking proper state licenses. And they did so from a property without proper zoning or permits, where tens of thousands of explosives were stored — and where local officials had apparent ties.
August 12, 2025: The investigation enters its seventh week. Records had unearthed a troubling gulf in California’s otherwise strict explosives’ oversight: the system depends on small, often underfunded, local agencies to enforce permits and inspections without providing much support to those agencies or double-checking their work.
August 22, 2025: Cal Fire permanently revoks the state licenses of both companies, Devastating Pyrotechnics and BlackStar Fireworks, operating at the blast site, citing multiple violations and escalating its criminal investigation.
The decision came as the agency reached its statutory deadline to either return or revoke the licenses it suspended shortly after the inferno. The agency has about 30 days after a suspension to make a determination.
August 29, 2025: Investigators from the Yolo County District Attorney’s Office search the home, office and vehicles of Esparto Fire Chief Curtis Lawrence as part of the criminal investigation into the fireworks explosion. A warrant, obtained by The Sacramento Bee and authorized weeks after the blast, was issued allowing prosecutors to seize Lawrence’s personal and work electronic devices, including his phone and computer. The search extended to the Esparto Fire Protection District’s station, Lawrence’s personal and professional vehicles, and his Esparto home.
To date, Lawrence has not been charged with any wrongdoing related to the deadly explosion.
September 2025: Reiko Matsumura, who served nearly 18 years as a deputy, retired from the Yolo County Sheriff’s Office, a department spokesperson confirmed to The Sacramento Bee.
She was not part of those arrested on April 9. But her sister and brother-in-law — Tammy and Sam Machado — were. Matsumura’s property just north of the compound with the Machado home also housed fireworks in several containers licensed by the Bureau of Alcohol, Tobacco, Firearms and Explosives that were not part of the explosion, The Bee previously reported.
Sept. 19, 2025: Senate Bill 828 is introduced by state Sen. Christopher Cabaldon, D-West Sacramento, and lists Assembly Majority Leader Cecilia Aguiar-Curry, D-Winters, who also represents the area, as a co-author.
The bill attempts to close two of the licensing “loopholes” that contributed to the lax oversight of the Esparto fireworks compound. It would require license holders to provide their local permits to Cal Fire and prevent people convicted of certain violent crimes from obtaining fireworks licenses.
October 2025: A report due January 2025 is turned in by officials with the Office of the State Fire Marshal, a division of Cal Fire. The report details how a lack of investigators limited the agency’s effectiveness in preventing large-scale incidents, that the cost of destroying growing stockpiles of seized illegal fireworks had outpaced its budget, and that local law enforcement across the state were unprepared to seize, store and report illegal fireworks.
However, it contained outdated figures and made no mention of the Esparto incident. The Cal Fire workload analysis shows the agency was fully aware of its regulatory shortcomings in the year leading up to the disaster.
Oct. 27, 2025: A search conducted by the Arson and Bomb Unit of Cal Fire’s Office of the State Fire Marshal alongside the Yolo County District Attorney’s Office discovered a cache of fireworks at a property owned by Luis Acosta in East Los Angeles prompting the evacuation of a high school and the surrounding neighborhood.
Dec. 1, 2025: California’s Division of Occupational Safety and Health, better known as Cal-OSHA, revealed it found 15 serious violations totalling $221,000 in fines to Devastating Pyrotechnics.
Dec. 23, 2025: The families of seven people killed in the fireworks explosion in Esparto file a $35 million claim against Yolo County, state fireworks regulators and several public officials, alleging widespread negligence that allowed an illegal and unsafe fireworks operation to continue. Those claims were denied.
December 2025: Ronald Botelho III is arrested in Crescent City. Botelho sold fireworks for Craig Cutright, a longtime show producer for Devastating Pyrotechnics who formed his own fireworks company, BlackStar Fireworks, in 2023.
Jan. 28, 2026: A state task force made up of representatives from local police and fire departments were issued wide-ranging recommendations aimed at tightening California’s fireworks laws and oversight. Among the issues flagged were licensing loopholes that allowed Devastating Pyrotechnics to import fireworks despite the owner’s prior conviction for a violent felony.
Feb. 2, 2026: California’s Office of the State Fire Marshal completed its investigation into the deadly fireworks explosion in Esparto and uncovered evidence of “illegal activity” and criminal wrongdoing.
Feb. 6, 2026: Lee Miller, the founder of Residents Against Illegal Fireworks, said the continuing revelations about the Esparto fireworks explosion has convinced her that an independent probe needs to look at the State Fire Marshal’s actions leading up to the fatal blast and its overall role in regulating fireworks. Miller wrote to Gov. Gavin Newsom, making the case for an independent investigation that would include examining Cal Fire’s oversight.
March 27, 2026: A task force of law enforcement and fire officials completed its review of legal and procedural shortcomings that contributed to the lax oversight of fireworks companies operating in Esparto. The final report made 37 recommendations aimed at improving public safety and reducing fires and injuries caused by fireworks.
April 9, 2026: Eight people were arrested in connection to the Esparto fire.
Samuel Elmo Machado and his wife Tammy Kiku Machado, who were both employed by the Yolo County Sheriff’s Ofice. They owned the property where fireworks were warehoused. Sam Machado was among five individuals charged with seven murder charges in connection to the blast.
Douglas Michael Tollefsen was also arrested and faces felony charges. He is an associate of Chee’s who allegedly helped import millions of pounds of explosives into the country from overseas before they were moved to Esparto to be repackaged and sold as consumer fireworks.
Kenneth Chee, the founder and CEO of Devastating Pyrotechnics, was also arrested. He was at Disney World’s Hollywood Studios near Lake Buena Vista, Florida, and was in the custody of the Orange County Corrections Department.
Jack Y. Lee, operations manager for Devastating Pyrotechnics, was arrested and booked into Yolo County.
Gary Y. Chan Jr., who obtained the federal explosives permit for Devastating Pyrotechnics, was arrested and booked into jail in Santa Clara County.
Craig Cutright, longtime show producer for Devastating Pyrotechnics and founder of BlackStar Fireworks faced 12 felony charges, including illegal possession of explosives, manufacturing destructive devices and conspiracy to commit a crime.
Ronald Botelho III was arrested in December in Crescent City and received additional charges in April, according to the Del Norte Sheriff’s Office, including felony reckless possession of explosives, conspiracy to commit a crime and making destructive devices without permits. Botelho sold fireworks for Cutright.
Machado, Chee, Tollefsen, Lee and Chan will be charged with murder.
This story was originally published April 10, 2026 at 3:11 PM.
