TEN suspects in a Tampines knife attack that left a 19-year-old boy with a gaping wound in his forearm a week ago were caught after a 30-hour police operation on Thursday.

And it turned out that the youths, aged between 14 and 22, are believed to be behind at least three cases of rioting with deadly weapons in Simei, Pasir Ris and Tampines between Feb 10 and 18, said police in a statement on Friday.

Seized from them were two daggers, three long bread knives and a parang.

In the Tampines slashing on Feb 16, the 19-year-old victim earlier told The Straits Times he and two friends were walking back from a friend's house at Block 263 in Tampines at about 11.45pm when they passed a group of about seven to nine other boys.

At Block 217 Tampines Street 21, the victim claimed one gang member walked up to him and took out a chopper, while the rest of the gang surrounded the trio.

'I was a bit kancheong (panicked) but I talked to them calmly. I tried to make them put down their weapons and see if we could talk it out,' said the youth, who only wanted to be known as Bob, from his hospital bed on Friday.

One of them then hit him on the back with a chopper handle and another slashed his left arm. The wound was so deep it needed 33 staples to close. The youth's muscles, nerves, veins and an artery were also damaged.

His two friends were unhurt.

'Police will not tolerate such irresponsible behaviour and total disregard for law and order,' said the assistant director of the Criminal Investigations Department (CID) for Specialised Crime, Deputy Assistant Commissioner Wong Choong Mann said.

Seven of the suspects will be charged in court on Saturday for rioting with deadly weapon, and the rest in the Juvenile court on Monday.

The offence carries a maximum jail term of 10 years and caning under the new amended Penal Code - an increase from the maximum of seven years previously.

Those found in possession of a scheduled weapon, which includes parangs, can be jailed for up to five years and caned not less than six strokes.

The joint operation was carried out by officers from the CID, Bedok Police Division and the Police Intelligence Division.