Tel Aviv - Two Israel Air Force pilots were killed when their helicopter crashed during a routine training flight Wednesday evening in northern Israel, the military confirmed.

The Cobra combat helicopter came down near a kibbutz in the Yezreel Valley, north of the town of Afula, some 10 minutes after taking off from a nearby Air Force base.

The two pilots were the only crew members on board. Their deaths were under military censorship until the families had been notified.

An Israeli military statement said that two Cobra helicopters were flying in formation when the formation leader suddenly saw the second chopper crash to the ground.

Israeli media reported that a technical problem appeared to have been behind the crash and quoted witnesses as saying they saw either the rotor or tail come off. The chopper caught fire and exploded when it hit the ground.

Air Force Commander Ido Nechushtan grounded all of Israel's Cobra helicopters until further notice and appointed a commission to investigate the incident. (dpa)