Tragic accident on the set of 'Expendables 2'

A terrible tragedy has taken place on the set of The Expendables 2, while filming in Bulgaria.

A stuntman was killed when an accident occurred involving a rubber boat and an explosion, MTV News reported.

The identity of the man who was killed has not yet been released. The accident took place when the second unit of the sequel was filming; none of the stars of the film were on set when the accident took place.

A statement was released by Image/Millennium Films that confirmed the event and stated that an investigation was underway to figure out why the accident took place, The Washington Post reported.

The Expendables 2 has been hailed as Arnold Schwarzenegger's comeback movie but the second installment in the action packed series seems to have already gained a bad vibe. After this tragic accident occurred it was announced that another stuntman was critically injured on set, Gather.com reported. No update has been posted on the condition of the stuntman post-accident.

The Expendables 2 is expected to hit theaters next August.