The family of a young economics graduate murdered for his iPhone told today how they found him dying on his doorstep.

Charity worker Abdul Samad, 28, stumbled to the front door of his block and buzzed for help after he witnesses said he was attacked in the street for his mobile by thugs on a moped.

His devastated brother, Abdul Ahad, told how his parents rushed to help him as he lay fatally injured outside his home in Little Venice.

He was taken to St Mary’s Hospital in Paddington, where he was born, but died an hour later.

Mr Ahad told the Standard how Mr Samad worked for charity Dragon Hall Trust helping young Londoners develop their computer skills.

He said: “He loved helping children. That’s the sort of person he was. This is a young life gone and such a lovely life. He was full of energy and loved the kids he worked with.

“You’re not going to find a nicer person. It was over a phone, it’s just so senseless.

“He came to the door here and buzzed and was covered in blood. The knife went through his heart.

“He pressed the buzzer and my mum and dad came down and he was lying there on the floor. My mum then called me and said ‘you’re brother is dying’.

“When I got here he looked half dead already.”

He added: “My brother has never done anything wrong and never been in trouble with the police.

"He was geeky and loved his computers and that’s why he was helping the young people.

“I could understand if it was some kind of postcode war but he’s not that type of person, his friends are all geeks.

“He was born in St Mary’s Hospital and he’s died there. We want these people to go to jail and never come out.”

He told how the parents of Mr Samad, who studied economics at the University of Westminster, originally settled from Bangladesh in the 60s in search of a better life for their children.

He had been at a friend’s house playing computer games before leaving because he had work early today.

However, the family said witnesses saw Mr Samad being approached by youths on a moped outside his flat in St Mary’s Terrace, who tried to steal his iPhone 7.

It is thought he may have been stabbed during a struggle at about 11.45pm last night. He was pronounced dead in hospital just before 1am this morning.

The friend said: “He was on his own only for a few metres after I left him after we got some food. He said he had to go home early because he had work early today.

“There were a couple of guys on mopeds who approached him, they’re always riding around here, and they tried to get his iPhone 7. We think he must have fought back or something.”

The killing came just hours after a young man was chased down and killed by a moped-riding assailant outside Parsons Green Underground station.

The 20-year-old was treated by medics but died at the scene in front of distraught family members who rushed to his aid, witnesses said.

Two other men were also taken to hospital after being stabbed in the first attack at around 7.30pm.

One witness, who did not want to be named, said: “I heard a load of shouting. There were two guys being chased up the road by a guy on a moped. He was on the pavement trying to run them off.

“The guy on the moped then drove on ahead under the bridge and started shouting “I’m going to f****** do you. The guy who was killed was shouting back.

“The victim had a face mask on, like a balaclava. Then the guy on the moped has jumped off. They’ve had an altercation and he’s put the other guy on the floor and stabbed him.”

Another witness said : “The bike mounted the kerb and the guy was shouting. The one that died looked as if he had been stabbed in the throat.

"People went to him and tried to stop the blood flow. He was revived about three times. Another guy was stabbed further up the road, it was carnage.”

Paramedics battled to save him but he died at the scene.

The incident took place a month after a bomb exploded at the District Line station during the morning rush hour. Although the bomb failed to fully detonate at least 30 people were injured.

Witnesses said the moped driver fled on foot before being accosted by a third man outside Parsons Fish Bar. Both men were reportedly stabbed in the incident.

Police said two men were taken to hospital with minor injuries. One remains in hospital while the other has been discharged and arrested in connection with the killing, police said.

Residents of the surrounding streets, where terraced houses sell for £2 million, were unable to enter their homes due to the large police cordon.

Anyone with information should call 0208 785 8099 or ring Crimestoppers anonymously on 0800 555 111.