Police say they have arrested a 26-year-old man who was a former staff member and that he has confessed to the stabbings but details of the motive have not yet been released.

At least 19 people have been killed and 45 wounded in Japan after a knifeman went on the rampage, according to reports.

The attack happened in the city of Sagamihara, west of Tokyo, where locals saw a man dressed in black clothes holding a weapon in the grounds of the Tsukui Yamayuri Garden.

It is thought that the building includes facilities for disabled people.

Four of the injured are said to be in a serious condition.

Police say they have arrested a 26-year-old man who was a former staff member and that he has confessed to the stabbings.

The suspect reportedly escaped the facility but then turned himself in. Details of the motive have not yet been released.

Officers swarmed the scene after receiving a call from staff just after 2.30am local time.

The attack comes after Japanese pop star Mayu Tomita was left in a coma in May after a fan stabbed her dozens of times because she reportedly refused his gift.

Police found a three-inch folding knife at the scene in western Tokyo.

A bloodstained mask and a trail of blood were found on the stairs near where the star was due to give a concert.

Tomohiro Iwazaki, 27, confessed to stabbing Tomita in the neck and chest.

He claimed he “ambushed” the star because she returned a gift he sent her.

In March last year, five people were also stabbed to death in a knife attack on a Japanese island.

A man was arrested after the victims were discovered in two houses.

Media reports said those killed range in age from 60 to 80 and lived in homes set among farms in the city of Sumoto on Awaji Island.

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