Police investigating the disappearance of a Hyogo woman Saturday found what appears to be her severed head in a suitcase left at a lodging facility in Osaka's Nishinari Ward.

The Hyogo Prefectural Police set up a special investigative unit for the case, which is being treated as abandonment of a corpse.

An American tourist named Yevgeniy Vasilievich Bayraktar, 26, was arrested in Nara Prefecture on Thursday on suspicion of confining the missing 27-year-old woman from Sanda, Hyogo Prefecture, in an apartment in Osaka's Higashinari Ward he was using as a vacation rental, investigative sources said.

"I never heard of a trouble here, so I'm surprised," said a 73-year-old resident of the building where the head was found, which houses mostly seniors on welfare benefits.

The investigators said security camera footage shows the two walking toward the Higashinari Ward apartment on Feb. 16. A camera inside also recorded the two entering together, but did not capture the woman leaving, the investigators said.