The federal probe into suspected illegal gun sales by local law enforcement officers involves at least four major police agencies in the Sacramento region, officials confirmed Friday.

Two deputies from the Sacramento County Sheriff's Department, one Sacramento police officer and one Roseville police officer are the focus of the probe that spilled into the open Thursday, the Bee has learned.

In addition, a Sacramento firearms dealer allegedly involved with some of the officers is under investigation, sources said.

Agents from the federal Bureau of Alcohol, Tobacco, Firearms and Explosives served a number of search warrants Thursday at officers' homes and a Sacramento gun shop.

At least three officers were placed on administrative leave Thursday: the Roseville officer and the two Sacramento County sheriff's deputies.

Roseville Police Sgt. Cal Walstad confirmed one officer from his agency was placed on leave but said he could not name the officer or provide further details. Two deputies who worked out of the Sacramento County sheriff's Rio Cosumnes Correctional Center also were placed on leave Thursday, sources told The Bee.

Sacramento police confirmed that one of their officers is under investigation in the case but would not release details. In addition, a California Highway Patrol officer based in the Sacramento region is considered a witness in the case, CHP spokeswoman Fran Clader said.

Sheriff Scott Jones said he understands the public has a lot of unanswered questions about the investigation, including the number and type of weapons involved, the relationship among the targets and the people to whom the guns were being sold illegally.

"Frankly, they're all legitimate questions," he said.

But Jones said he cannot speak in detail about the case because it is ongoing and because the ATF is the lead agency. Previously, he told The Bee that ATF officials had asked him not to talk about the case.

"It's frustrating to not be able to talk about it, but this investigation, even though it involves deputies, I have to treat it like every other investigation," Jones said. "At the right time, I will – I'll get up and say as much as I can say, and I look forward to that opportunity."

No charges have been filed, and no one has been arrested, but at least one of the deputies retained a high-profile Sacramento defense attorney, William Portanova, on Friday.

Portanova, a former federal and Sacramento County prosecutor, confirmed he is representing the deputy but declined to identify him or discuss the case.

ATF spokeswoman Helen Dunkel confirmed Thursday night that her agency was in the midst of an ongoing investigation that could lead to indictments but declined to provide details.

Sources have told The Bee the investigation is targeting officers who used their positions to purchase weapons that are not available to the public, then sold them for profit.

An officer seeking to make such a purchase can go to a licensed gun dealer with authorization from his chief or sheriff without having to go through a 10-day waiting period or background check, said Sam Paredes, executive director of Gun Owners of California.

For instance, law enforcement officers can purchase weapons with magazines that carry more than the 10-round limit, Paredes said. They also can purchase semiautomatic weapons that are not permitted to be purchased by the public.

The extent of the alleged sales and the types of weapons involved has not been made public and the search warrants issued in U.S. District Court in Sacramento have been sealed.

However, one source said Thursday's searches had been fruitful and that indictments were expected.

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