The Taliban claimed in a statement on Tuesday that its fighters have shot down a NATO CH-47 Chinook military transport helicopter in southern Afghanistan.

Witnesses cited by a Taliban spokesman said all people on board were killed when the chopper crashed on Monday afternoon in Zabul province.

There were no details available on how many NATO personnel were aboard, but the spokesman said they were returning to base after a mission. Several NATO countries fly Chinooks, including the US, UK and Netherlands.

Iranian Press TV reported a U.S. military helicopter made an emergency landing in Zabul province on Monday. The International Security Assistance Force (ISAF) operating in Afghanistan has not commented on the incident.

The insurgents often exaggerate success of their attacks on ISAF forces or claim accidental losses of ISAF aircraft as shoot-downs.