Israeli antiquities authorities operating under heavy police guard began relocating ancient graves on Sunday to make way for construction of a hospital emergency room, setting off protests from ultra-Orthodox Jews who say Jewish remains are being disturbed.

Officers forcibly carried off dozens of demonstrators who had staged a sit-in to try to stop the work outside Barzilai Hospital in the southern city of Ashkelon. Police spokesman Micky Rosenfeld said 30 protesters were arrested.

Archaeologists have determined the graves belonged to Christians or pagans from the Byzantine period, about 1,400 years ago. But ultra-Orthodox Jews insist they are Jewish bones that should not be moved, in accordance with religious practice.