A medical student was stabbed to death in a greengrocer’s in South London after a dispute over a stolen orange, his family said yesterday.

Khalil Nasseri, 24, was visiting the shop, which was owned by his cousin Asad, on Saturday when he was attacked by a gang of men. The cousin claimed that one of the men had tried to steal an orange from the shop, in Brixton, two days earlier.

According to his cousin, Khalil, who had nothing to do with the alleged original dispute, was standing outside MS Nasseri Quality Fruit and Vegetables, helping two other people to clear up, when all three were set upon. He was stabbed and the other men were attacked with a hammer.

Mr Nasseri, who had studied medicine in his native Afghanistan, wanted to follow in his father’s footsteps and become a doctor. He was described as intelligent and talented.

Asad Nasseri, Khalil’s cousin and the owner of the greengrocer’s at the corner of Atlantic Road and Electric Avenue, said: “On Thursday a black man had come into the shop and tried to walk out without paying for an orange. There was an argument and the guy left, saying, ‘I’ll be back’. I think he left because he felt outnumbered. He was alone and there were four or five of us.”

According to the owner of a neighbouring shop, who did not want to be named, the man returned to the greengrocer’s later that evening with seven or eight others, but found it closed. The neighbour said: “There was a whole gang of them, but there was nobody at the shop by the time they got there.”

But on Saturday evening Khalil was visiting his cousins and helping them to close the shop for the day. Asad said: “At about 7.30pm, Khalil and two others were standing outside the shop, clearing up. [They] just came up to them and started to stab them without saying a single word.

“They stabbed Khalil from behind and attacked the other two with a hammer and knives. Khalil had not even been in the shop on Thursday evening when the argument happened. He was just a visitor on Saturday and happened to be there at the wrong time. He had nothing to do with it.

“The guy was looking for an argument and found Khalil.”

Police confirmed that the suspects were all black males but were unable to say how many were involved or how old they were. A post-mortem examination yesterday revealed the cause of death to be a stab wound to the heart.

Mr Nasseri came to England in 2003. His cousin said he was planning to return to Afghanistan to finish his degrees and get married. He said: “Khalil was a gentleman. He was so intelligent and talented and was studying to become a doctor like his father. He loved watching movies and hanging out at the shop with his family. He was looking forward to going back to Afghanistan soon.”

Another shop owner said: “Arguments in this area in shops happen a thousand times a day. It is normal, but why did this man come back to kill?”

Police said that they were keeping an open mind about the motive behind the stabbing.

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