Police investigating the murder of a young Tamil father at a child’s birthday party believe a fight between teenagers about a botched drug deal may have led to his death.

Akilankumar Kanthasamy, a 28-year-old Sri Lankan immigrant from Harrow, was stabbed in the heart at about 11.30pm on Saturday night, at the New Horizon Centre, a community centre in South Lodge Avenue, Mitcham.

The party was attended by mostly Tamil families of all ages for one-year-old Shania Sinnathurai, the daughter of a Sri Lankan couple from Liverpool who came to Mitcham to celebrate with their relatives in Thornton Heath.

Addressing a public meeting last night for Tamil residents in Mitcham and Thornton Heath, Detective Inspector Steve Wilcox revealed a Tamil youth who was attending the party had offered to sell cannabis to a black youth outside the community centre some time before 9pm.

After the black youth left to get money to buy the drugs, he turned up with a group of four or five more youths who then rob the Tamil teenager of a couple of bags of cannabis.

This led to a fight at about 11.30pm in the rear car park a couple of hours later between a group of Tamils and a group of black youths in which a knife was drawn.

Mr Kanthasamy, who had nothing to do with this altercation, was stabbed as he went outside to his car which was parked in the car park.

Det Insp Wilcox explained: “Mr Kanthasamy has nothing to do with that fight. He is just there at the party enjoying himself. I believe he is come outside to make sure his car is not damaged.

He added: “Mr Kanthasamy comes from Harrow. The lad selling this cannabis comes from Leigh Green in Lewisham. Your community may not have a lot of involvement with these people at the party.

“I don’t think you should be fearful for your safety. You should be vigilant as you always are.”

As of this morning (Friday), four arrests have been made: an 18-year-old woman and two boys aged 17 and 16. A 16-year-old was arrested on Monday but was released on bail.

Det Insp Wilcox said all four youths come from the Pollards Hill estate.

A second knife has now been recovered but the detective leading the investigation, Detective Chief Inspector Mark Dunne, said on Tuesday he believed the murder weapon had been recovered.

Det Ch Insp Dunne also said the lighting was so poor at the rear car park where Mr Kanthasamy was stabbed that footage from a CCTV camera could not be seen.

Det Insp Wilcox confirmed that the camera was not a night vision camera and would only be able to show daytime footage.

A Merton Council representative said the area had two cameras, one of which is a motion detection camera and is “not high resolution”.

Mitcham and Morden MP Siobhain McDonagh, who organised last night’s meeting at St Michael’s Church, Chestnut Grove, said she would organise a summit for Pollards Hill residents to address wider issues of safety and policing.

Mum speaks of grief after birthday party descends into horror

“It was such a happy night but now my friend is dead and I feel guilty. If there was no party he would still be alive today.”

Those tragic words were delivered through tears this week by a young mother who simply wanted to celebrate the birth of her one year old daughter in front of friends and family in Thornton Heath.

Instead, the dozens of mostly Tamil guests who attended the party at the New Horizon Centre on Saturday night were subjected to a horror show in which a young family man collapsed to the ground after being stabbed in the heart.

Saranjah Sinnathurai, 23, said the party she had organised had been “wonderful” and was going so well that her husband asked the security guard if they could stay a few minutes longer than 11pm, when the party was supposed to end.

Mrs Sinnathurai said: “Akilankumar was a such a nice guy. He was soft spoken, quite short and very kind. He would never hurt anyone.

“I saw his wife Parmita yesterday and she was so upset and I felt so sorry for her because she is only 22 with a young baby. But I told her I would do what I could to help her.

“I just keep thinking what I would do if it was my husband. First we are having a happy celebration but now someone is dead and we can’t understand why. “

Recalling the moment when Mr Kanthasamy stumbled into the community centre, she said he was clutching his chest and was barely able to speak.

She said: “He came in and was speaking very softly [in Tamil]. He said that someone had got him with a knife then he just dropped to the floor like it was slow motion.

“Then he didn’t move and everyone was very scared. There was so much blood, so much blood. We were trying to shake him but it was no good.

“Lots of people were calling 999 and the police came very quickly, but the ambulance did not come for 25 minutes. We were very scared.”

Her husband, Baskaran Sinnathurai, who lives in Liverpool with his wife and child but stayed with relatives in Thornton Heath specially for the party, said he was outraged and certain the killing was an unprovoked attack.

He said: “Akilankumar was very gentle with good manners. We don’t understand why this has happened; we would never look for trouble.”

Any witnesses, or anyone with any information about this tragic incident, should call the Incident Room on 020 8721 4906 or Crimestoppers anonymously on 0800 555 111.

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