"At 6 p.m. (1500 GMT) yesterday, our fighters shot down a Cobra helicopter," Ahmed Danees, so-called head of foreign relations for the outlawed Kurdistan Workers Party (PKK), told Reuters by telephone.
He gave no details of casualties but said more information would be released later. The incident had occurred during fighting in the remote Chamsku area close to the border, Danees said.
"The clashes are still ongoing. Yesterday evening there was artillery shelling and air strikes on the PKK inside Iraq," he added.
On Saturday, Danees claimed PKK militants had killed 22 Turkish soldiers since Turkey began a cross-border offensive into Iraq's largely autonomous Kurdistan region on Thursday.
He said PKK militants had recovered the bodies of 15 of those killed and the militants would also release their names soon.
Turkey's military General Staff has said in a statement on its Web site that only seven Turkish troops had been killed, while its forces had killed 79 PKK militants.
Verifying information about casualties is difficult as the fighting is taking place in an inaccessible mountain region.
Güncelleme Tarihi: 24 Şubat 2008, 12:19