The reopening date of one of Japan’s most popular zoos has been pushed back amid an investigation into an employee allegedly burned his wife’s body on-site.

The man in his 30s reportedly confessed to police that his wife’s body was in the incinerator of Hokkaido’s Asahiyama Zoo in Asahikawa, as reported by local newspaper Asahi Shimbun.

The employee’s wife was reported missing in late-March, when an associate was unable to contact her.

As part of the investigation, authorities questioned her husband, an employee of the zoo, on April 23, when he confessed to using the incinerator to dispose of her body.

The pair lived together in Asahikawa.

The zoo was searched by police on April 24, and the employee’s home was searched two days later.

The incinerator at the popular attraction was used for the carcasses of animals that died.

According to South China Morning Post, local media said the man told police he “disposed of the body in the zoo’s incinerator and burned it for several hours”.

A truck with the zoo’s logo is believed to have transported the body, and two other vehicles have been seized.

Originally scheduled to reopen on April 29, the zoo will now remain closed until at least May 1 while police search for the body of the missing woman, whose body has not yet been found.

Since April 8, it has been closed to the public as staff removed winter enclosures and performed seasonal maintenance.

On April 28, Asahikawa Mayor Hirosuke Imazu apologised for the “great inconvenience” caused to those planning to visit and called the decision to delay the opening “painful”.

He warned that “sudden closures or limiting access to certain areas” may be necessary throughout the investigation.

The BBC reported that the mayor described the situation as an “unprecedented crisis”.

“No one could have predicted it,” he said.

“I am overcome with immense anxiety, and I am facing a crisis of unprecedented magnitude.

“We are making preparations to welcome you, so we hope that as many people as possible will come to the park.”

Asahiyama Zoo was opened in 1967 and saw 1.33 million people through its gates last financial year.

City officials have reportedly provided mental health support for zoo employees, and animals are being cared for.