One of Japan’s most popular zoos has delayed its reopening after an employee reportedly told police he had burned his wife’s body in an incinerator on its grounds.

Asahiyama Zoo in Hokkaido’s second-largest city of Asahikawa, which had been closed for a seasonal break since April 8, was set to reopen on Wednesday, a national holiday. But the date has been pushed back to at least Friday to allow police to search for the body, according to The Asahi Shimbun newspaper.

At a news conference on Tuesday, Asahikawa Mayor Hirosuke Imazu said the city was cooperating with the police investigation. He apologised to visitors planning to visit the city-run zoo over the Golden Week holidays for the “great inconvenience”, calling the postponement “a painful decision”, as quoted by the newspaper.

The case came to light last week after a friend of the man’s wife asked police for a welfare check as she had been unreachable since late March. The woman, who was in her thirties, had sent phone messages to friends saying she was afraid because her husband had threatened her, News on Japan reported, citing people familiar with the matter.

Following the report, Hokkaido prefectural police on Thursday interrogated her husband, an Asahiyama Zoo employee in his thirties. During questioning, he allegedly hinted at his involvement in her death, according to the news outlet.

He told police he had “disposed of the body in the zoo’s incinerator and burned it for several hours”, Hokkaido Television Broadcasting reported.

Police started searching the zoo, including the incinerator at its animal hospital, on Friday and the family home in Ashikawa on Sunday but have not found the body. A truck bearing the zoo’s logo, believed to have been used to transport the body, and two other vehicles have been seized, according to The Japan Times.