The aircraft was returning from an operation in Afghanistan

A US Navy plane with four crew members on board has crashed into the Arabian Sea, the US Fifth Fleet said.

It said in a statement that the E-2C Hawkeye aircraft experienced mechanical malfunctions, forcing the crew to perform a controlled bail-out.

Three of the four crew were later recovered and a search is now under way for the fourth crew member.

An investigation has been launched into the incident. The crew was stationed on the USS Dwight D Eisenhower.

The aircraft had crashed into the sea at about 1400 local time (1000 GMT) on Wednesday, the statement said.

It said the plane "was returning from conducting operations in support of Operation Enduring Freedom" in Afghanistan when the problems had occurred.

The identities of the crew are being withheld pending notification of next-of-kin.