Five people remain hospitalized Sunday after a medevac jet carrying a child patient and her mother crashed into a residential neighborhood in Philadelphia Friday night, killing seven people and leaving dozens injured.

A medevac plane crashed soon after takeoff in Philadelphia on Friday with a child and five others on board, the air ambulance company that operated it said, adding that it had not confirmed any survivors.

Investigators have not been able to locate the aircraft's black box yet, which could provide clues into the cause of the crash.