Adelaide, Australia ? A marine researcher was missing and presumed dead Wednesday after he was attacked by a shark off a popular beach near the southern Australian city of Adelaide, police said.

Two researchers from Adelaide University were diving to collect cuttlefish eggs when the shark attacked. Two other people in the research team’s boat saw the shark coming and managed to haul one diver to safety, but they could not prevent the second from being attacked about 1 1/4 miles off Glenelg Beach.

Police in boats scoured the sea where the attack happened and found the missing diver’s oxygen tank and buoyancy vest, but they gave up the hunt for his body as night fell.

The divers’ identities were not released and there was no information available on the type of shark involved.