A French journalist who was held by the Islamic State says one of the jailers during his 2013 captivity is the same man who police say killed four people in an attack on the Jewish Museum of Belgium in May. The accused gunman is also French, increasing fears in Europe over European citizens' ties to extremist groups.

From Brussels, Teri Schultz reports:

"French reporter Nicolas Henin and his fellow former hostages have told investigators Mehdi Nemmouche was one of their captors — and a brutal one, who tortured them mercilessly. This, according to Henin's story in French newsmagazine Le Point, his employer when he was kidnapped in Syria in 2013 and held for almost a year. Henin revealed last month that he was sometimes detained with murdered American journalists James Foley and Steven Sotloff."Nemmouche is believed to have walked into the Brussels Jewish Museum in broad daylight in May and gunned down four people, escaping back to France before he was arrested. He has admitted he spent time on the battlefield in Syria. Nemmouche is in jail in Belgium and will go before a judge on Friday on charges of murder and terrorism."

Before now, Henin and other former hostages have avoided disclosing details about their captors' identity, out of fears that Westerners still being held by IS could face retaliation, according to Le Point.

But the story emerged this weekend, after Le Monde published an account about a government investigation tying Nemmouche to the extremist group. Both of the French news outlets note that while other journalists agreed with parts of Henin's account, some details and levels of certainty differed among them.

Describing his ordeal, Henin said, "When Nemmouche wasn't singing, he tortured," according to Le Point. He said that Nemmouche was one of several French citizens who helped run the makeshift prison that held journalists and dozens of Syrians in a former hospital. They routinely beat the prisoners, he said.

"The torture lasted the night," Henin said, "up until the dawn prayer."

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