An EagleMed medical helicopter crashed near a hospital in the US state of Oklahoma Tuesday night, killing one and injuring the rest three on board, local media reported.

The accident took place at 6:30 pm local time (1130 GMT) near the Choctaw Nation Hospital in Talihina, a town about 225 km from state capital Oklahoma City, the hospital's spokesperson Brandy Griffin told local media. There were no casualties on the ground.

Among the injured, one was in critical condition and was flown to a neighboring hospital, while the two others were treated at the hospital.

Federal authorities were sending investigators to the scene while the identities of the victims have not been released.

It is still unknown where the aircraft departed from.