The commander of the Al-Qaeda affiliated Al-Nusra Front was killed in car bomb at the Yarmuk Palestinian refugee camp south of Damascus, Arabic satellite TV channel Al-Arabiya reported on Friday, citing activists.
Abu Yousef al-Hourani and his deputy died when a bomb planted in al-Hourani's car exploded, according to the report.
Activists at Yarmuk posted photos of the blast to the Internet, Al-Arabiya said.
The Al-Nusra Front, one of the most powerful armed groups in Syria, launched an attack on Yarmuk in April and controls part of the camp.
Yarmuk was once a thriving neighbourhood of Damascus, home to both Palestinian refugees but also Syrians.
But after fighting erupted in the camp, the Syrian government in 2013 imposed a blockade and the area's population shrank from 160,000 to just 18,000.