BEIRUT (AP) — A Syrian opposition group says Lebanese Hezbollah fighters have killed a senior member of the Islamic State group.

The Syrian Observatory for Human Rights said Tuesday that the man known as Abu Abdullah al-Iraqi was killed by a bomb planted in his car in the rugged Qalamoun region along the border with Lebanon.

Hezbollah's Al-Manar TV reported al-Iraqi's death but said he was killed in a "qualitative" operation carried out by the Syrian army. It said he was in charge of rigging cars with explosives and preparing suicide bombers which he sent to Lebanon.

The Shiite group, a longtime staunch ally of the Syrian government, is heavily involved in fighting alongside President Bashar Assad's forces in Syria.

The group typically does not claim responsibility for operations inside Syrian territory.