Former All Black Jerry Collins was sweating heavily and appeared anxious as he went behind a shop counter in Japan and placed a knife on it in front of frightened staff, witnesses say.

The Herald can reveal more details on how the 32-year-old ended up in a Japanese jail after carrying the knife into the Entetsu department store in Hamamatsu City.

A manager of the store, Katsuyuki Aono, said staff told him Collins entered the food department in the basement of the store about 5pm on Saturday.

He went behind a service counter, which is off limits to customers, and worried staff called security.


"When the security guard from our store arrived, Mr Collins pulled out a knife and placed it on the counter," Mr Aono said. "The security guard then took the knife and called the police."

Officers arrived and arrested Collins.

Mr Aono said he didn't know why Collins went behind the counter but he frightened the staff in the store.

"He was perspiring heavily and appeared very anxious and unstable. He was acting very strange and was looking around in different places behind the counter.

"He was speaking in English, but the staff couldn't understand what he was saying."

Collins wasn't violent and didn't threaten or touch any of the staff - nor did he try to take money from the register, Mr Aono said.

"We really couldn't understand what he was doing - he was just behaving in a strange and abnormal way. Saturday early evening is a busy time for our store and there were a lot of customers."

Mr Aono said staff did not recognise Collins. "We were very surprised to hear that this man was a famous All Black from New Zealand. We hope he is able to recover soon and return to playing rugby."


Collins would be kept in police custody for at least 10 days but it could be up to 20, police said.

"We are currently questioning Mr Collins and trying to ascertain what happened," a spokesman told the Herald. "We are trying to find out why he was in possession of a concealed weapon ..."

Once police have finished questioning Collins, they will pass on the information to the public prosecutor who will decide whether to lay formal charges.

"Mr Collins will remain in custody at the Hamamatsu Police Station for at least 10 days," the spokesman said.

"If need be, he will then be detained for an additional 10-day period for questioning as is allowed under Japanese law."

Collins is being held in Japan's substitute police prison system.


Under the country's archaic prison law, suspects can be held in custody for 23 days from when they are first brought to the station before formal charges are laid.

* Read the Herald's live news blog here.