AN 18-year-old champion kickboxer from Dundalk, who was beaten to death last week, will be awarded an honorary black belt at his funeral mass.

Gardaí investigating the murder of Niall Dorr, from Avondale Park in Dundalk, believe up to six people were involved in the fatal assault.

The teenager died less than 24 hours after being assaulted by a group of people on Wednesday night. He died from head injuries.

Three people were in custody in relation to his killing this weekend. Bernard Duffy, an instructor at Cobra-Kan kickboxing club in Dundalk, paid tribute to the teenager, who was due to turn 19 within weeks.

"He was a member of the club since he was eight years old. He was extremely talented and dedicated. He regularly came down and helped train the younger kids. He was a great character and a very honest and quiet young man. Everyone at the club is absolutely devastated," he told the Sunday Tribune.

"He found out on Tuesday that he passed his medical to get into the army and he was so pleased. He was extremely dedicated to getting a career in the army. He qualified for the world kickboxing championship in Portugal but was taking some time out to concentrate on getting into the army. The club will form a guard of honour at his funeral mass. He had got to the level of brown belt in kickboxing. We will present him with an honorary black belt at his funeral."

A source said the murder investigation is at a critical point and the next seven days will be vital.