The United States and its coalition partners conducted eight air strikes against Islamic State militants in Syria and seven in Iraq since early Thursday, according to the US military.
In a statement on Friday, the Combined Joint Task Force leading the air operations said the strikes near al Raqqah, Kobani and Dayr az Zawr in Syria hit numerous armored vehicles used by the militant group as well as two units of fighters, among other targets.
In Iraq, the air strikes near al Asad, Mosul and Sinjar hit five units of Islamic State fighters, three buildings, three fighting positions and other targets, according to the statement.
The Iraqi security forces, meanwhile, repelled an attack by Islamic State insurgents against an air base in Anbar province where US marines are training Iraqi troops, Iraqi and US military officials said.
Militants from the jihadist group had attacked the Ain al-Asad base and the nearby town of al-Baghdadi a day earlier, leading to sporadic clashes in the town overnight. Al-Baghdadi has been besieged for months by Islamic State, which captured swathes of northern and western Iraq last year, prompting a campaign of US-led air strikes and the deployment of hundreds of US military advisers to the country.
A US defence official said the Iraqi forces had stopped the attack and re-secured the facility.
"Coalition forces were several kilometres from the attack and at no stage were they under direct threat from this action," the official said.
About 320 US marines are training members of the Iraqi 7th Division at the base, which has been struck by mortar fire on at least one previous occasion since December.
Iraq's defence ministry said on its website the Iraqi army killed eight assailants near the base, which is about 85 km (50 miles) northwest of Ramadi.
Prime Minister Haider al-Abadi, a moderate Shi'ite Islamist who since taking office in September has promised to support the neglected Sunni minority community, said the army was prioritising the western Sunni province in its fight against Islamic State.
"The Iraqi government and security forces are extremely concerned with Anbar, its defence and the protection of its residents from Daesh," he said on his official Facebook page, using a pejorative acronym for the ultra-radical Sunni group.
An Iraqi military official in Baghdad told Reuters the insurgents had taken advantage of a lull in the air strikes caused by poor weather to launch the offensive, but that weather had since improved.
The US military said the United States and its coalition partners conducted seven air strikes against Islamic State militants in Iraq between early Thursday and early Friday, including five strikes about 15km east of Ain al-Asad base.
The Iraqi official said Islamic State had been cleared from most of al-Baghdadi, with the remaining fighting centred around a police station.
That conflicted with reports from a tribal leader who said the jihadists were still in control of much of the town. Ongoing clashes and poor communications in the area made it difficult to confirm such reports.