BEIRUT: Rebels downed a helicopter gunship in a key area of northwest Syria on Wednesday, a monitoring group said, as the army fought to take back control of the key town of Maaret al-Numan from the Free Syrian Army.

"In Maarhtat, on the outskirts of Maaret al-Numan, rebel fighters downed a helicopter being used in the fighting," said the Syrian Observatory for Human Rights. "According to initial reports, the helicopter crashed in nearby Bsida."

Maaret al-Numan, strategically located in the northwestern province of Idlib, has been under rebel control since last week.

The town is on the highway linking Damascus to embattled Aleppo, Syria's second city and commercial hub.

The rebel blockade of the highway is preventing regime reinforcements from reaching Aleppo, which has been the theatre of intense fighting for the past three months.