A U.S. Postal Service truck apparently broadsided a car carrying five people in downtown Minneapolis Sunday night, injuring four of them seriously, police said.

The accident happened about 9 p.m. at the intersection of 5th Avenue S. and S. 4th Street, police Sgt. William Palmer said.

The truck driver, who was the only occupant of the truck, received minor injuries; all six people involved in the accident were taken to Hennepin County Medical Center, Palmer said.

Their conditions were unavailable late Sunday.

The cause of the accident remains under investigation.

HERÓN MÁRQUEZ ESTRADA