AMMAN, Jordan -- A car bomb ripped through Syria's largest city, Aleppo, on Sunday, killing at least 17 people and wounding 40 in one of the main battlegrounds of the country's civil war, state-run media said.

Al-Qaida-style bombings have become increasingly common in Syria, and Western officials say there is little doubt that Islamist extremists, some associated with the terror network, have made inroads in the country as instability has spread. But the main fighting force looking to oust President Bashar Assad is the Free Syrian Army, a group made up largely of defecting Syrian soldiers.

Though no group immediately took responsibility for the attack Sunday, it came hours after a Jordanian militant leader linked to al-Qaida warned that his extremist group would launch "deadly attacks" to help the rebels in Syria topple Assad.

In a speech delivered to nearly 200 followers protesting outside the prime minister's office in Amman, Mohammad al-Shalabi, better known as Abu Sayyaf, told Assad that "our fighters are coming to get you."

The warning fueled concern that Syria's civil war is providing a new forum for foreign jihadists, who fought alongside Iraqi Sunni insurgents after the 2003 invasion of Iraq and are sending fighters to help the Taliban in Afghanistan.

A Jordan-based Western diplomat, who monitors Syria from his base in Jordan, said the number of foreign fighters is about 100 and is gradually rising.

"From this podium, we declare jihad [holy war] against the wicked Assad, who is shedding the blood of our Sunni Muslim brothers in Syria," Abu Sayyaf yelled through a loudspeaker.

Abu Sayyaf heads Jordan's Salafi Jihadi group, which was blamed for the 2002 assassination of U.S. aid worker Laurence Foley outside his Amman home. Sayyaf was convicted in 2004 of plotting attacks on Jordanian air bases hosting American trainers, served his term and was released last year.

The fight for Aleppo, a city of 3 million that was once a bastion of support for Assad, is critical for both the regime and the opposition.

Its fall would give the opposition a major strategic victory with a stronghold in the north near the Turkish border. A rebel defeat, at the very least, would buy Assad more time.

On the latest episode of "Sarra Sounds Off," the Suffolk Hall of Fame class of 2026, former NFL Quarterback Mike Buck and Jared Valluzzi has the plays of the week. Credit: Newsday Credit: Newsday

Sarra Sounds Off: Suffolk Hall of Fame Class of 2026 On the latest episode of "Sarra Sounds Off," the Suffolk Hall of Fame class of 2026, former NFL Quarterback Mike Buck and Jared Valluzzi has the plays of the week. Credit: Newsday

On the latest episode of "Sarra Sounds Off," the Suffolk Hall of Fame class of 2026, former NFL Quarterback Mike Buck and Jared Valluzzi has the plays of the week. Credit: Newsday Credit: Newsday

Sarra Sounds Off: Suffolk Hall of Fame Class of 2026 On the latest episode of "Sarra Sounds Off," the Suffolk Hall of Fame class of 2026, former NFL Quarterback Mike Buck and Jared Valluzzi has the plays of the week. Credit: Newsday

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