SHARI, Japan -- Police found what appeared to be several human bones Thursday on the western tip of Hokkaido's Shiretoko Peninsula during an intensive search for people still missing after the sinking of the Kazu I sightseeing boat in April, the Hokkaido prefectural police said.

The police plan to carry out DNA tests to determine any connection with the accident.

The search -- conducted on the shoreline near Keikichi Bay by a team of about 25 people -- also found child- and adult-sized sneakers, a hat, a key chain and a set of keys, among other items. Checks will be made to determine if the items belonged to Kazu I passengers.

Originally scheduled to begin Tuesday -- four months after the accident -- the search was moved up to Thursday after local fishermen found what appeared to be a human skull in Keikichi Bay on Sunday.

Brown bears frequent the tip of the peninsula, so the police drafted in hunters before conducting the search on foot. Divers and underwater drones are planned to search local waters on Saturday.

The 1st Regional Coast Guard Headquarters also conducted a search Thursday of the coastal area of the peninsula and found several bone-like objects and a black bag. DNA tests are planned to determine if the remains are human.