Three operators of US military attack helicopters were killed when their aircraft crashed in central Alaska while returning from a training flight, the Washington Post reported late Thursday night (this morning Greek time), citing sources close to the armed forces.

The two Apache AH-64s, based at Fort Wainwright“crashed (…) near Hilli, Alaska, while returning from a training flight,” the command of the US Army’s 11th Airborne Brigade said in a press release.

Emergency crews “are on site. The incident is under investigation and more information will be released as soon as it is available,” the statement continued, without specifying if or how many victims there are, nor the causes of the accident.

Apaches have two-man crews, consisting of the pilot and the sensor and weapons operator.

It is not known at this stage if the fourth soldier was injured or if he is safe.

Reuters news agency tried to contact military officials for comment, but they did not immediately respond.

This is the second such accident within a period of less than one month.

In late March, nine US service members were killed when two Black Hawk helicopters of the US Army crashed during night high schools in Kentucky (center).

Moreover another Black Hawk helicopter crashed in mid-February in Alabama (south), killing both occupants. That last helicopter, belonging to the Tennessee Air National Guard, was also conducting a training flight near a freeway and another thoroughfare. The causes of the accident were not announced.