US airstrikes ISIS
The US-led coalition airstrikes are designed to weaken the military capabilities of the militant group.AFP

The US-led coalition against Islamic State have carried out over 15 aerial bombings last night, hitting a number of key Islamic State (Isis) targets in both Iraq and Syria.

US officials confirmed that seven strikes had been executed in Syria and eight in Iraq.

Several units of Islamic State fighters and a number of important buildings were successfully targeted by US-led coalition jets.

Last week, coalition jets carried out 10 air strikes in Syria and seven in Iraq. Eight of the strikes struck contested border territory near the besieged town of Kobani.

Falluja, Tal Afar and Sinjar were some of the areas hit in Iraq.

News of the latest air strikes comes after Syrian activists reported that 120 foreign fighters had been executed by Islamic State in the past three months for attempting to leave the extremist group.

According to the London-based Syrian Observatory for Human Rights (SOHR), at least 120 fighters have been killed by Islamic State. This number could be higher with Rami Abdurrahman, director of SOHR, suggesting "from our sources on the ground, we believe that over 200 have actually been killed".

Abdurrahman told The Independent: "We can confirm that 120 fighters have been killed by Isis, but from our sources on the ground we believe that over 200 have actually been killed."

According to the report, the victims were executed for "exceeding the limits in religion", most likely fighters who chose to give up jihad and desert Islamic State.