DAMASCUS - The US-led coalition widened its air strikes against the Islamic State group in Syria on Saturday as part of "near continuous" raids against the jihadists.
The targets were said to include IS fighters around the mainly Kurdish town of Ain al-Arab where a jihadist advance has sent 160,000 refugees streaming into nearby Turkey.
The coalition also hit IS in the central province of Homs for the first time as well as in the town of Minbej, near the western limit of the group's control, the Syrian Observatory for Human Rights said.
The expanded operations in Syria by Washington and its Arab allies came after three more European governments deployed fighter jets for strikes against IS in Iraq, freeing up US air power.
Belgium, Britain and Denmark approved plans to join France and the Netherlands in carrying out air raids against the militants in Iraq, allowing Washington to focus on the more complex operation in neighbouring Syria, where IS has set up its headquarters.
But Washington warned that the jihadists could not be defeated in Syria by air strikes alone, saying that up to 15,000 "moderate" rebels would need to be trained and armed to beat them back.
It was the second time that US-led air strikes had been reported around Ain al-Arab since the launch of the IS advance.
According to state media and the Observatory, there were also strikes around the town on Tuesday night.
Syrian Kurds welcome strikes
Senior Syrian Kurdish official Newaf Khalil told AFP the latest strikes hit the IS-held town of Ali Shar, east of Ain al-Arab, and destroyed several IS tanks.
"We definitely welcome... the international coalition in the fight against (IS)," Khalil told AFP via the Internet.
The strikes came a day after hundreds of Kurdish fighters crossed from Turkey to reinforce Ain al-Arab's Kurdish militia defenders, breaking through the border fence with Turkish security forces apparently turning a blind eye.
The coalition also pounded the Euphrates valley city of Raqa, which the jihadists have made the headquarters of the "caliphate" they declared in June straddling swathes of Iraq and Syria.
"At least 31 explosions were heard in Raqa city and its surroundings," said the Observatory, a Britain-based monitoring group which has a wide network of informants on the ground.
Observatory director Rami Abdel Rahman said the targets hit in Homs province meanwhile were in the eastern desert far away from the front line in fighting involving forces loyal to President Bashar al-Assad who control Homs city, Syria's third largest.
Washington has been keen not to let Assad's forces exploit the air campaign against IS to take the upper hand in the more than three-year-old civil war.
The United States and Arab allies launched air strikes against IS in northern and eastern Syria on Tuesday, more than a month after Washington began its air war on the jihadists in Iraq.
Washington had been reluctant to intervene in Syria's raging civil war, but was spurred into action as the jihadists captured more territory and committed widespread atrocities, including the beheadings of three Western hostages.