LEIDEN, NETHERLANDS—The University of Leiden announced that artifacts its researchers unearthed during the past 25 years at the Syrian site of Tell Sabi Abyad may have been stolen from storage depots in the provincial capital of Raqqa by armed men. The artifacts include 6,000-year-old pottery and art objects, and animal and human remains—much of it unstudied. “I cannot check the extent of the damage because due to all the violence the area is too dangerous to enter. Since December of last year, I have not been able to contact the Syrian guard of our depots,” Peter Akkermans told the NL Times. Akkermans has no word about the condition of Tell Sabi Abyad, either.