The US military said four troops were killed and two others injured in a mid-air collision of two helicopters in southern Afghanistan.
Hostile fire was ruled out in the crash, which occurred this morning. No further details are being released.
In an unrelated incident, another helicopter went down today during a joint, international security force operation against insurgents in western Afghanistan in which a dozen militants were killed.
The US said military casualties were reported and a recovery operation is under way.
COMMENT RULES: Comments that are judged to be defamatory, abusive or in bad taste are not acceptable and contributors who consistently fall below certain criteria will be permanently blacklisted. The moderator will not enter into debate with individual contributors and the moderator’s decision is final. It is Belfast Telegraph policy to close comments on court cases, tribunals and active legal investigations. We may also close comments on articles which are being targeted for abuse. Problems with commenting? firstname.lastname@example.org