PHILADELPHIA (CBS) - Authorities are investigating an accident in the city’s Feltonville neighborhood that left four people injured Thursday afternoon.

Police say a school bus and a car collided at about 4 p.m. near G and Ramona streets.

Two children on the bus were injured and taken to St. Christopher’s Hospital for Children in unknown condition.

Two men in the car were sent to Temple University Hospital in critical condition, according to police.

There is no word on how the accident happened.