EAST BRUNSWICK — State Police are looking for the car that caused a school bus returning from a picnic to overturn on the New Jersey Turnpike on Saturday.

The bus was in the left lane of the northbound outer lanes approaching Route 18 when a blue sedan came from behind and veered out of its lane, hitting the left guard rail after 5:30 p.m., according to State Police spokesman Sgt. 1st Class Jeff Flynn.

The car went back into traffic and struck the bus on the driver's side, causing it to hit a Mercedes before it overturned between the inner and outer lanes, Flynn said. The car left the scene, he said.

Flynn did not have a description of the car yet.

The bus was one of eight returning to Newark from the annual Mayor’s Family Reunion/Picnic at the Black Bear Lake Country Club in Millstone. Newark Mayor Ras Baraka said at a press conference on Saturday night that "several thousand" usually attend the picnic.

"It scared us half to death," Baraka said of the overturn.

Thirty-six of the 42 adults and children were taken to Robert Wood Johnson University Hospital in New Brunswick, JFK Medical Center in Edison and St. Peters University Hospital in New Brunswick, police said.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ