The Islamic State group released a video Sunday showing what appeared to be footage of the people behind the terrorist attacks in and around Paris last November while they were in Iraq and Syria. In the newly released video, the men, some of them European citizens, carried out executions, including a beheading, before the attacks in France, the New York Times reported.

While it was previously known some of the suspects had traveled to Syria, it was unclear whether the attacks that left 130 people dead were ordered by the leadership of the militant group aka either ISIL or ISIS. The video seemed to be an attempt to clear up suspicion the attacks may have been carried out by an independently acting sleeper cell.

SITE Intelligence Group said the video appeared to have been recorded in Raqqa, the de facto capital of the Islamic State group in Syria, BBC News reported. Nine of the individuals in the video resembled the suspects in the Paris terrorist attacks, SITE said.

The Islamic State group is believed to have thousands of supporters living in Europe, with returnees from Iraq and Syria among them. However, the sophistication of the attacks in France indicated a well-coordinated plot that was likely drawn up in Syria, experts said.

The six coordinated attacks marked the largest terrorist event since the militant group’s rise in the Middle East. There appeared to be two primary sites targeted by the terrorists: a concert hall and a soccer stadium. More than one-half of the deaths happened during an attack on the Bataclan concert hall.

The attackers were armed with AK-47 rifles and were wearing suicide-bomber vests. The Islamic State group claimed responsibility for the attacks the morning after they were carried out. Nine attackers died during the attacks, while two remain at large.

The release of the latest video came just a week after the extremist group published the newest issue of its propaganda magazine, Dabiq, showing a still image from the video. The militant group has frequently released videos showing its members in Iraq and Syria carrying out executions, most often of alleged spies or political opponents.