A US defense official told AFP on condition of anonymity that American warplanes carried out one air strike near Baghdad and another near Mount Sinjar, in the north of Iraq, in the past 24 hours.
The United States last month began a campaign of air strikes against IS positions in northern Iraq, but Monday's announcement that US warplanes had targeted the militants near Baghdad marks an escalation in the scope of the mission.
"US military forces continued to attack ISIL (IS) terrorists in Iraq, employing attack and fighter aircraft to conduct two airstrikes Sunday and Monday in support of Iraqi security forces near Sinjar and southwest of Baghdad," US Central Command said in a statement.
"The air strike southwest of Baghdad was the first strike taken as part of our expanded efforts beyond protecting our own people and humanitarian missions to hit ISIL targets as Iraqi forces go on offense, as outlined in the president's speech last Wednesday."
The strikes destroyed six IS vehicles near Sinjar and an IS fighting position southwest of Baghdad that had been firing on Iraqi forces.
"All aircraft exited the strike areas safely," the statement added. "These strikes were conducted under authority to protect US personnel and facilities, support humanitarian efforts, and help Iraqi forces on the offensive against ISIL terrorists."
They bring the number of US air strikes across Iraq to 162. The news comes as the world's top diplomats pledged to support Iraq in its fight against IS by "any means necessary", including "appropriate military assistance."
The international community is scrambling to contain the IS jihadists, who have rampaged across Iraq and Syria and could number as many as 31,500 fighters, according to the CIA.
Stay updated on the go with The Times of India's mobile apps. Click here to download it for your device.