The family of a teenage boy stabbed to death in the street have paid tribute to their loved one saying, "every day, every second we will be thinking of him".

Nilanthan Moorthy, 17, was stabbed in the early hours of Saturday morning.

He died of a single knife wound to the neck after the incident on Sumner Road, in Croydon, south London.

His sister Santhiya, 18, said his parents were "destroyed".

Mother Kalaimagal Moorthy flew back from a trip to India on hearing the news and his Father Ramuppillai was said to be repeating the words "he's gone" over and over again.

Santhiya, a waitress in the family business, the Royal Masala restaurant in Purley, said her parents were "terrible, destroyed".

"Words can't express how I feel right now," she said.

"He was energetic, always giving a helping hand whenever it was needed.

"Everyday, every second we will be thinking of him."

Nilanthan, from New Addington, Croydon, was taken by ambulance to Mayday Hospital, where he was pronounced dead.

Police believe a man who argued with the teenager and his group of friends may have returned shortly afterwards to carry out the attack.

Nilanthan had been studying maths and English A-levels at Langley Park Girls' School, which has places for boys in the sixth form, but he left to help in the family business, where he worked as a waiter.

Other family members said he enjoyed playing football, cricket and pool, as well as cracking jokes.

He was "really energetic" and "the joker of the family".

Detectives are seeking a mini cab driver who they believe could be a vital witness.

The driver, believed to have been in a blue Ford Mondeo, stopped at traffic lights behind another car.

Police believe his passenger, a white man, argued with him and "exchanged words" with Nilanthan and his friends who were standing nearby.

A Metropolitan Police spokeswoman said: "The suspect returned a little while later and was again involved in an exchange of words with Nilanthan and his friends, which resulted in the victim being injured."

A 31-year-old man arrested in connection with the murder was released on police bail pending further inquiries.

Nilanthan's death brought the toll of teenagers who have died violently in the capital this year to 23.

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