Story highlights French prosecutor says Mehdi Nemmouche was radicalized by Islamist teachings while in prison

Suspect was detained with bag full of items related to the killings, prosecutor says

An Israeli couple from Tel Aviv and a French woman died in May 24 shooting

The shooter also wounded a museum worker

Police have arrested a suspect in Marseille, France, in connection with the shooting deaths of three people May 24 at the Jewish Museum in Brussels, Belgium, Belgian federal magistrate Wenke Roggen said Sunday.

The suspect is identified as Mehdi Nemmouche, a 29-year-old Frenchman from Roubaix in the Pas-de-Calais region of northern France.

Nemmouche recently spent a year in Syria and is a radicalized Islamist, the chief prosecutor of Paris said at a news conference Sunday.

Francois Molins said Nemmouche, who has a criminal history that included a five-year prison stint, was detained at the St. Charles Train Station on Friday after returning to France by bus from Brussels by way of Amsterdam.

Molins said customs police detained Nemmouche after discovering a Kalashnikov assault rifle in his luggage and a revolver in a black bag he was carrying.

Nemmouche, who has remained silent during his detention, was influenced by Islamist teachings while in prison and left for Syria three weeks after being released in September 2012, Molins said.

French officials lost contact with him when he left the country.

Photos: Photos: Shooting at Jewish Museum of Belgium Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – Police have arrested Mehdi Nemmouche, a 29-year-old Frenchman, in Marseille, France, in connection with the shooting deaths of three people on May 24 at the Jewish Museum in Brussels, Belgium, according to Belgian authorities. Hide Caption 1 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – Three people were killed and a fourth was critically injured in the May 24 shooting. Here, people pay their respects Sunday, May 25, in front of a makeshift memorial at the entrance of the museum. Hide Caption 2 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – A man places a candle in front of the entrance of the museum on May 25. Hide Caption 3 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – A man wipes away tears during a vigil in front of the museum on May 25. Hide Caption 4 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – A woman lays flowers at the museum entrance on May 25. Hide Caption 5 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – Police cordon off the area near the museum after the shootings on Saturday, May 24. Hide Caption 6 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – In this hand out photo distributed by the Belgian Federal Police, a surveillance camera shows the suspected killer near the museum on May 24. Hide Caption 7 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – The photographs and video released by police show the suspect wearing a cap and blue shirt, carrying two bags over his shoulder. The images do not show his face clearly. Hide Caption 8 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – Police and crime scene investigators work at the scene of the shootings on May 24. A person arrived by car at the museum, entered and quickly opened fire before leaving, Belgian Interior Minister Joelle Milquet told CNN affiliate Bel RTL. Hide Caption 9 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – Officers and investigators work in an cordoned-off area of the scene on May 24. Hide Caption 10 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – Forensic experts examine the shooting site on May 24. Hide Caption 11 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – The circumstances of the shooting have raised suspicions that it might have been an anti-Semitic attack, but no motive has been determined. Hide Caption 12 of 13 Photos: Photos: Shooting at Jewish Museum of Belgium Shooting at Jewish Museum of Belgium – Investigators work the shooting scene after the museum and its surroundings were sealed off. Hide Caption 13 of 13

JUST WATCHED Belgium's Jewish community security fears Replay More Videos ... MUST WATCH Belgium's Jewish community security fears 02:19

JUST WATCHED Video shows Jewish Museum gunman Replay More Videos ... MUST WATCH Video shows Jewish Museum gunman 01:49

JUST WATCHED 3 dead in shooting at Jewish museum Replay More Videos ... MUST WATCH 3 dead in shooting at Jewish museum 02:52

In addition to the rifle, prosecutors said, the suspect's luggage contained ammunition for the Kalashnikov and a white cloth with Arabic writing on it.

Bullets and cameras

In the black bag Nemmouche was carrying when he was detained, along with a .38 special, police discovered 57 rounds of ammunition for the revolver, more than 270 cartridges for the Kalashnikov, gun parts, a portable GoPro camera, a digital Nikon camera, a black hood and gloves, a Nike cap, a gas mask, and a blue nylon jacket, all objects matching the description of the Brussels shooter.

Investigators also made another discovery during the examination of the items in Nemmouche's bags, prosecutors said. They found a hidden file on the Nikon camera containing a 40-second video that showed the two weapons that were seized, the clothing worn by the shooter, and the GoPro camera.

Although the suspect does not appear on the film, prosecutors said there is an audio commentary. They believe it is Nemmouche's voice heard commenting on the images on screen and explaining that the video was made because the recording of the shooting at the Jewish Museum with the GoPro camera did not work.

Two of the victims who died in the attack were an Israeli couple in their 50's from Tel Aviv, Israel's Foreign Ministry has said. The third victim was a French woman.

A fourth person, a Belgian national who works at the museum, was shot and injured.

Caught on camera

Images from the museum in Brussels showed the gunman behind last week's deadly attack approaching the building, opening fire, and walking away.

He used an AK-47 assault rifle to carry out the shooting, police have said.

Photographs and video released by Belgian police showed the man wearing a cap and blue shirt, carrying two bags over his shoulder. The images do not show his face clearly.

The shooter left on foot after the attack and headed toward a different part of downtown Brussels before he disappeared, according to police.