A US military helicopter has crashed in rural eastern England killing all four crew members.<br /><br />The Pave-Hawk aircraft which is a modified version of the Army Black Hawk, is said to have been on a night time low-level flying exercise when it went down on the north Norfolk coast. <br /><br />No one on the ground was injured.<br /><br />British police immediately secured the area suspecting live ammunition may have been on board.<br /><br />The helicopter was based at nearby RAF Lakenheath. The cause of the crash is unknown.
