CAIRO: The self-styled Islamic State group claimed responsibility on Tuesday for a weekend attack at a centre near Dallas, Texas, exhibiting cartoon depictions of the Prophet Muhammad (PBUH).

An audio statement on the extremist group's Al-Bayan radio station said that “two soldiers of the caliphate” carried out Sunday's attack, and promised to deliver more in the future.

The statement did not provide details and it was unclear whether the group was opportunistically claiming the attack as its own.

It was the first time the Islamic State, which frequently calls for attacks against the West, has claimed responsibility for one in the United States.

Two suspects in Sunday's attack in the Dallas suburb of Garland were shot dead after opening fire at a security guard outside the center.

Read more: Texas police shoot dead two gunmen at Prophet (PBUH) caricature exhibit

It was unclear whether the group, which has captured large swathes of territory in Syria and Iraq, had an actual hand in the operation, or whether the two suspects had pledged allegiance to the group and then carried out the attack on their own.

The suspects have been identified by officials as Elton Simpson and Nadir Soofi.

They opened fire in on an unarmed security officer stationed outside the contest center.

According to Islamic tradition, any depiction of the Prophet (PBUH) is considered blasphemous, and drawings similar to those featured at the Texas event have sparked violence around the world.

Read more: Police raid home of gunman killed in Texas attack incident