The Latest: Activists say militants in Syria down warplane

The Latest on the fighting in Syria that's threatening to undermine a U.S.-Russia-brokered cease-fire that has held for over a month (all times local)

Syrian activist groups are reporting that militants have shot down a warplane in northern Syria.

The Britain-based Syrian Observatory for Human Rights says it isn't clear whether the warplane that was downed on Tuesday is Russian or Syrian.

The Local Coordination Committees says it was downed near the northern village of al-Ais was Syrian. Both groups, which monitor the Syrian civil war, gave no word about the crew.

Russian warplanes have been carrying out airstrikes in Syria since Sept. 30. Syrian militants have not downed any Russian planes. Neighboring Turkey, however, shot down one Russian aircraft last year.

Syrian rebels have shot down several Syrian warplanes since the country's crisis began in March 2011.