A deadly car bomb targeted a Turkish convoy in an area of northern Syria controlled by Turkey-backed fighters on Wednesday, a Britain-based war monitor said.

A car bomb killed nine people including four civilians in a Turkish-held border town in northern Syria on Saturday, a Britain-based war monitor said.

The Israeli military said it intercepted four incoming rockets from Syria on Tuesday and explosions were heard shortly after that in Damascus, a week after another Israeli strike targeted a top Palestinian militant in the Syrian capital.

Israeli air defense systems captured the projectiles, the military said, and no harm was caused to Israeli communities in the Golan Heights after warning sirens awoke residents there early in the morning. There was no immediate official comment from Syria but the SANA state news agency reported explosions were heard near Damascus International Airport, indicating a potential Israeli retaliatory strike.

As U.S. troops beef up in eastern Syria to protect oil fields, residents hope their mission will bring stability and prosperity to the remote and resource-rich region —and keep the Syrian government out.

Their hopes reflect the expectations being piled onto the operation, even as President Donald Trump flip-flopped on the scope and duration of troops deployment. He initially ordered all troops out of Syria last month, then decided to keep a force in place to hold the oil infrastructure.

The number of US troops in Syria remains roughly stable at just under 1,000 three weeks after President Donald Trump announced their withdrawal, a US official said Monday.

The withdrawal of American troops from Syria's northern border opened the way for Turkey's military incursion against Kurdish forces in the country.

An air strike Saturday by key Damascus ally Russia killed six civilians including a child in the embattled opposition bastion of Idlib in northwestern Syria, a war monitor.

US forces patrolled part of Syria's border with Turkey on Thursday in the first such move since Washington withdrew troops from the area earlier this month, an AFP correspondent reported.

Russian President Vladimir Putin met his Turkish counterpart Recep Tayyip Erdogan on Tuesday to discuss the situation in northern Syria, where Turkey has vowed to resume an offensive against Kurdish fighters.

Iran on Monday denounced as "unacceptable" any move by Turkey to establish military bases in Syria, saying such a step would face opposition from the Islamic republic and other countries.

U.S. Vice President Mike Pence met Turkish President Recep Tayyip Erdogan on Thursday to push for a ceasefire in Syria after Ankara rebuffed international pressure to halt its deadly offensive against Kurdish forces.