A 450-acre vegetation fire is burning at Mammoth Bar Park in Auburn as of Thursday evening.

Initial reports indicate fireworks started the fire.

Multiple crews are responding to the incident at about 2:30 p.m. Thursday.

Officials reported 40 percent containment Thursday night.

California Highway Patrol had closed Old Foresthill Road between the Confluence and Foresthill Road as of 3:30 p.m. However, the Highway 49 bridge connecting Auburn to Cool remained open as of 4:30 p.m.

Foresthill Road off Interstate 80 has also been closed.

Placer County Sheriff’s Office deputies are currently evacuating Grizzly Range, the American River Confluence and the Lake Clementine Recreational Area, according to Sheriff’s spokeswoman Dena Erwin.

About 375 fire personnel have responded to the call, 325 of which are Cal Fire crew members. Cal Fire also reported 25 engines, 12 fire crews, five air tankers, four helicopters, three dozers and four water tenders responded. An additional two engines not from Cal Fire assisted as well as three non-Cal Fire dozers.

The Placer County Sheriff’s Office, California State Parks, California Highway Patrol and Placer County Water Agency were listed as cooperating agencies.

According to Cal Fire’s online incident report, there are no known threats to communities at this time.

Citrus Heights resident Jim Leimbach and his family and friends were stopped at about 4 p.m. just short of turning onto Foresthill Road in Auburn.

The crew, complete with two campers pulled by pickup trucks loaded with dirt motorcycles, was headed to Morning Star Reservoir in Foresthill for a weekend of camping.

When they turned off the Interstate 80 exit for Foresthill Road, a Placer County Sheriff’s deputy was directing traffic away from driving onto the road.

“As soon as we got here, they shut it down,” Leimbach said.

The Leimbachs pulled into a nearby parking lot and watched as the billowing gray cloud of smoke grew before them.

“We’ll sit and here and wait until it opens or go home,” Leimbach said. “One or the other.”

The Journal will update the story as more information becomes available.

The Journal's Jenifer Gee can be reached at jeniferg@goldcountrymedia.com or post a comment.