The Tuesday attack may ignite a new round of infighting between terrorist groups in the war-torn country.

The so-called Syrian Observatory for Human Rights said Ali al-Nuaimi of the Nusra Front -- al-Qaeda's affiliate in Syria -- and his wife were killed overnight while travelling in the southern Daraa province, AP reported.

The bombing took place near the town of Busra al-Sham, according to the Observatory, which described the killing as an "assassination."

The Nusra Front did not mention the attack on the social networks it typically uses.

The attack came after Nusra terrorists seized a controversial Western-backed Syrian military commander, Ahmad al-Nuaimi last Friday. It is unclear if the two men are related - the al-Nuaimi is a large tribe in the area. Also, it wasn't immediately clear if the two incidents were connected.

The bombing and the abduction risk igniting militant infighting in the south between rival terrorist groups including Nusra Front.

The abducted commander, Ahmad al-Nuaimi, was widely disliked by many terrorists who accused him of abandoning his men in battle in the past and fleeing to Jordan.

A radical organization calling itself the "Islamic Courts of the Eastern Areas - Daraa" has confirmed it has Ahmad al-Nuaimi and another military commander, saying it would soon air their "confessions."

BA/BA