Failing brakes on a big rig caused a pile up on the Highway 99 offramp at Main Street Tuesday morning, leaving four people injured.

None of the injuries were considered life-threatening, according to the Turlock Fire Department.

The accident was reported just before 7:30 a.m. Tuesday at the southbound offramp.

A big rig traveling along the highway developed a mechanical malfunction and lost braking ability. The driver exited at the southbound offramp, but was unable to stop and struck a pickup truck, a sports utility vehicle and a car stopped at the intersection of W. Main Street.

The big rig continued across the intersection and up the onramp before coming to a stop, reported Turlock Fire Capt. David Bickle.

Initially the accident was reported as having major injuries with multiple people pinned inside vehicles, but when the first emergency responders arrived at the scene, the majority of the people involved in the accident were out of their vehicles walking around the site. No extrications had to be performed.

A total of seven people were involved in the pile up. Two people were treated for neck injuries and were transported to the hospital. Two others had minor injuries and were transported for treatment as well. The other three declined treatment.

While all the people managed to escape from the crash without serious damage, the same could not be said of the vehicles. The three vehicles struck by the big rig suffered extensive damage. The fire department estimated the damage at $170,000.

A total of three fire engines, four ambulances and 12 fire fighters responded to the scene.

The California Highway Patrol closed the offramp for a few hours.