Crews are on the scene of a three-vehicle accident, involving a jackknifed big rig, that has closed all southbound lanes of Highway 99 near Eschinger Road south of Elk Grove.

The Cosumnes Fire Department reported the accident via Twitter at 4:11 p.m.

Caltrans reported collision on southbound Highway 99 in Elk Grove just north of Dillard Roard, with a detour at Grantline Rd.

“Avoid SAC SB 99 if possible. Multiple crashes have traffic backed up for several miles,” the state Department of Transportation reported on Twitter.

Google traffic shows traffic at a standstill from north of Elk Grove Boulevard to south of Twin Cities Road.

“The accident has resulted in a traffic back up on 99 to Elk Grove Blvd, and it is continuing to grow. Use alternate routes,” the Cosumnes Fire Department said on Twitter.

This is a story in progress. Check back soon at sacbee.com for more information.