AKIPRESS.COM - Rebels in southern Syria announced a major offensive on Wednesday to capture remaining positions held by the Syrian military in Quneitra province, near the Israeli-occupied Golan Heights, where bombardments could be seen a short distance away.

Quneitra sits in a sensitive region around 70 kilometers (40 miles) southwest of the capital Damascus and has been the scene of frequent fighting between various insurgent groups and the Syrian military backed by allied militia.

Rebel spokesman Issam al-Rayes wrote on Twitter that an alliance of insurgent groups fighting in the operation had signed a pact, which did not involve al Qaeda's Syria wing Nusra Front.

The groups in the offensive are fighting under the banner of the rebel Free Syrian Army, he said. Nusra has fought in southern Syria but is not thought to be the main insurgent force there, unlike in other parts of the country.

A Reuters photographer watching from the Israeli-occupied Golan said there had been heavy shelling since early Wednesday in the Quneitra area, with scores of bombardments.

At one point he could see smoke rising from around 13 bombardments and the sound of small arms being fired could also be heard in the distance.

The shelling appeared to be focused between Quneitra's water reservoir and the town itself, with some buildings on the outskirts appearing to have suffered damage, the photographer said. It was not clear which groups were taking part.

Later, rocket alarms sounded in the Golan Heights, a Reuters photographer said. Tanks on the Syrian side could be seen firing their cannons in the reservoir area and there was the sound of Syrian helicopters overhead, reported Reuters.