A man arrested on suspicion of killing four people last month at the Jewish Museum of Belgium allegedly claimed responsibility for the attack in a video.

Belgian federal prosecutor Frederic Van Leeuw said June 1 in a news conference in Brussels that a video found after the May 29 arrest of Mehdi Nemmouche, 29, in Marseille includes his voice claiming responsibility for the May 24 attack and murders. Nemmouche had tried to film the attack, according to Van Leeuw, but the camera failed.

Nemmouche is being held on suspicion of terrorist activity. At the time of his arrest he carried a small, portable video camera and a baseball cap similar to the one that is believed to have been worn by the perpetrator of the Brussels Jewish museum shooting, according to Agence France-Presse.

Nemmouche became a radical jihadist while serving a sentence in France in 2009 for armed robbery, French television reported. He left France for Belgium in 2012 and from there traveled to Syria.

Roger Cukierman, president of French Jewry’s umbrella organization CRIF, told the British Independent newspaper that it would be a “huge relief” if Nemmouche is found to be the Brussels killer.

“While he was free, another attack was likely,” Cukierman said. “It seems that the worst fears of Western governments are being realized. The European jihadists in Syria are a time bomb waiting to go off.” — jta