Two U.S. Army helicopters returning from a training flight collided in Alaska on Thursday, leaving three soldiers dead and a fourth injured. 

The incident was the second such accident involving military helicopters in the state.

Each AH-64 Apache helicopter involved in the crash was carrying two people, according to John Pennell, a spokesperson for the U.S. Army Alaska.

"This is an incredible loss for these soldiers’ families, their fellow soldiers, and for the division," Maj. Gen. Brian Eifler, commanding general of the 11th Airborne Division, said in the Army statement. "Our hearts and prayers go out to their families, friends and loved ones, and we are making the full resources of the Army available to support them."

MILITARY HELICOPTER CRASH IN AK INJURES 2 SOLDIERS

The names of those killed are being withheld until relatives are notified, the Army said.

The crash occurred near Healy, Alaska, while returning to Fort Wainwright, near Fairbanks. The cause of the crash is under investigation.

Healy is located about 10 miles north of Denali National Park and Preserve and approximately 250 miles north of Anchorage.

In a statement from Joint Base Elmendorf-Richardson, Alaska, the helicopters were part of the 1st Attack Reconnaissance Battalion, 25th Aviation Regiment at Fort Wainwright.

First responders arrived on the scene, and the incident is under investigation.

In February, two soldiers were injured when a military helicopter – an Army AH-64D – was involved in a rollover accident in Talkeetna, Alaska.

The helicopter was also part of the 25th Attack Battalion at Fort Wainwright.

In March, nine soldiers were killed when two U.S. Army Black Hawk helicopters crashed during a routine nighttime training exercise. 

The helicopters were part of a medical evacuation unit. The crash took place approximately 30 miles northeast of Fort Campbell, Kentucky.

The Associated Press contributed to this report.