French police have pinned down a self-declared jihadist believed to be the killer of seven people in southwestern France in the past 10 days—including three small children and a rabbi outside a Jewish school in Toulouse on Monday. The suspect has been barricaded inside a house in eastern Toulouse, where officials say he has claimed membership with al Qaeda. French Interior Minister Claude Guéant said the 24-year-old justified the fatal shootings of the four people outside the Ozar Hatorah school as “revenge for Palestinian children,” and indicated that the killings of three soldiers in two previous attacks were intended as vengeance against the “French army because of its foreign interventions.” The siege began at around 3 a.m. local time on Wednesday, and reports indicate the heavily armed assailant may be preparing to give himself up. French police indicated that he’s resumed talking to negotiators.

According to news reports, Guéant said the suspect—a man of Algerian descent identified as Mohammed Merah—is known to have traveled to the border area between Pakistan and Afghanistan for training with radical Islamist groups that he claims membership with, notably al Qaeda. Reuters is reporting that the suspect had been jailed in Kandahar, Afghanistan, in 2007 for planting bombs, but escaped months later during a Taliban prison break. Both his identity and overseas travel had been known to French intelligence services, though it hadn’t been felt he was an immediate security threat. French anti-terrorism officials have told TIME repeatedly—including recently—that a number of young men from the Toulouse region are among several in France known to have sought or succeeded in obtaining armed training in Iraq, Pakistan, Yemen and other “theaters of jihad.”