BEIRUT (AP) -- Al-Qaida-linked gunmen killed a rebel commander in Syria aligned with the Western-backed militias fighting against Bashar Assad's regime, the highest-profile casualty of growing tensions between moderate and jihadi fighters among rebel forces.
Observers worried Friday that the commander's death will increase distrust and suspicion between forces already at odds over territory and leadership as the nearly three-year civil war continues in Syria.
Loay AlMikdad, a spokesman for the Free Syrian Army, said Friday that members of the Islamic State of Iraq and the Levant -- a group reportedly made up of al-Qaida's branches in Iraq and Syria -- were behind the killing of Kamal Hamami. Hamami, known as Abu Basir, served in the Supreme Military Council of the Free Syrian Army, a group headed by a secular-minded moderate that has the support of Western powers.
The Britain-based Syrian Observatory for Human Rights said gunmen shot Hamami dead late Thursday after militants tried to remove a checkpoint he set up in the Jabal al-Turkoman mountain in the coastal province of Latakia. The observatory said two of his men were seriously wounded in the shooting.
AlMikdad told Al-Arabiya TV that Hamami "was assassinated at the hands of the forces of evil and crime at one of the checkpoints." He added that the group that killed Hamami "should hand over those who carried out this act to stand trial."
Activists monitoring the war previously reported occasional clashes between rebel groups and Islamic militants active in rebel-held areas, especially in the north where the opposition has control of a large part of the region. There also has been infighting between Kurdish and Arab groups over control of territory captured from government along the border with Turkey in the past year. That fighting subsided after a cease-fire agreement early this year.
Hamami's killing marks the first time a commander from the Supreme Military Council of the Free Syrian Army has been killed by rebel jihadists. His death underlines a deepening power struggle between moderate and extremist groups fighting in the Syrian civil war.
"It's hard to tell where things are going to. It could really go either way," said Charles Lister, an analyst at IHS Jane's Terrorism and Insurgency Center. "I personally don't think it's in either of the sides' longterm interest to spark an escalation."
Rami Abdul-Rahman, who heads the observatory, said that most of the Islamic State of Iraq and the Levant members are foreigners. He said they come from Arab countries as well as former Soviet republics such as Chechnya.
Last week, Abdul-Rahman said members of the group killed a local rebel commander, Fadi al-Qish, in the village of Dana in the central province of Hama.
"They spend money to spread their influence among people," Abdul-Rahman said.
The same group killed a 15-year-old youth in the northern city of Aleppo last month, accusing him of being an "infidel" for mentioning Islam's Prophet Muhammad in vain. Gunmen shot the boy dead in front of a stand where he sold coffee, sparking international concern about religious extremism creeping into the ongoing civil war.
More than 93,000 people have been killed since the Syrian conflict began in March 2011 with largely peaceful protests against Assad's rule that escalated into a civil war in response to a brutal government crackdown. Over the past year, the conflict became increasingly sectarian, with mostly-Sunni rebels assisted by foreign fighters fighting government forces bolstered by fighters from the Lebanese Shiite group Hezbollah.
Assad's government is backed by Russia and Iran. Moscow has continued to supply Assad with weapons throughout the crisis, saying it is fulfilling existing contracts. The U.S., as well as its European and Gulf allies, has backed the opposition in the conflict, sending funds and non-lethal aid to the rebels.
Turkey and Iran -- at odds over the crisis in Syria -- jointly called Friday for a cease-fire in the country during the holy Muslim month of Ramadan, which began Wednesday. Turkish Foreign Minister Ahmet Davutoglu and his Iranian counterpart, Foreign Minister Ali Akbar Salehi, made the appeal in the Turkish capital, Ankara.
Iran is a strong ally of Assad. Turkey has backed the Syrian opposition, including rebels fighting government forces. Davutoglu also called for all non-Syrians involved in the conflict -- including Iranian-backed fighters from the Lebanese Shiite group Hezbollah -- to leave Syria.
Also Friday, several mortar shells hit the central Amara neighborhood in the capital Damascus, killing at least six people and wounding dozens, according to the SANA state news agency. It reported that shells fell on the residential area and that at least 40 people were wounded and taken to hospitals.
Associated Press writer Suzan Fraser in Ankara, Turkey, contributed to this report.
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