AMMAN (Reuters) - A leading figure in al Qaeda who became a prominent member of its Syrian Nusra Front offshoot was killed in a drone attack on Monday, the group and jihadist sources said.

They said Sheikh Abu al Faraj al Masri, who spent years in prison in his native Egypt on charges of plotting with fundamentalist Islamist groups and later left for Afghanistan, died when the vehicle in which he was traveling was hit in rebel-held Idlib in Syria’s northwest.

“May God accept him as a martyr who was killed in a Crusader raid,” said a jihadist named Abu Mohammad al Shami.

The U.S. Defense Department said in a statement that Masri was the target of a U.S. air strike near Idlib on Monday. “We are still assessing the results of the strike,” it said.

Since the U.S.-led coalition launched operations in Syria, primarily against Islamic State militants, air strikes have also targeted Nusra Front figures, killing scores.

Syria’s militant Jabhat Fateh al Sham, formerly the Nusra Front, confirmed the death of the Egyptian cleric in an air strike.

In one of Masri’s last public appearances, he was alongside former Nusra leader Abu Mohamad al-Jolani when the group announced in July it was renaming itself Jabhat Fateh al Sham to deny Washington and other powers a pretext to attack it.

Washington dismissed that move as cosmetic and said it would continue to target it as a terrorist group.

Last month, Abu Hajer al Homsi, the group’s top commander, was killed in an air strike in rural Aleppo province.

Masri, 60, whose real name was Sheikh Ahmad Salamah Mabrouk, had been one of the leading companions of al Qaeda leader Ayman al-Zawahri in Afghanistan in the late 1980s, according to a jihadist source.

Masri was one of the early leaders of the radical militant Egyptian Islamic Jihad movement. He was arrested after the assassination of Egyptian President Anwar Sadat in 1981 and spent seven years in prison.

Masri was also held secretly under a CIA rendition scheme after his arrest in Azerbaijan in 1998.

The source said that like some other jihadists, he came to Syria to join Nusra Front after being freed from an Egyptian prison during the rule of President Mohamed Mursi, an Islamist toppled by the military in 2013 after mass protests against his rule.