A rescue operation is underway after a truck fell off the Delaware Memorial Bridge and into the river on Friday, July 11. The accident involved no other vehicles but left one lane of traffic closed, causing morning delays.

WILMINGTON, Del. -- A tractor-trailer cab crashed through a concrete barrier Friday and plunged off the Delaware Memorial Bridge into the Delaware River, authorities said. It wasn't clear how many people were in the cab, which was found in about 20 feet of water, according to the Delaware River Bay and Authority.