A man in his 60s has been stabbed to death in west London. The Metropolitan police said a man in his 30s has been arrested on suspicion of murder after the incident on Saturday evening in Southall.

The man was pronounced dead at the scene in St Mary’s Avenue and his family has been informed. The arrested man is in hospital where he is under police guard and being treated for minor injuries.

The victim was stabbed after leaving a pub in a leafy suburb, a witness who gave him first aid said. Raj Grover, who lives nearby, said he was about to go to his 41st birthday party when the man knocked at his door with stab wounds.

“He was ringing our doorbell,” he told PA Media. “He rang the bell and I went out, my son was there, he was shouting, ‘dad, come out.’ I went downstairs and saw he (the victim) was full of blood, and then I was running to pick up a towel. I put the towel on and I was pressing to stop the blood, then my wife came out, we called the ambulance and the police.”

Scotland Yard said police were called at 6.41pm and the victim was treated by paramedics and air ambulance crews, but died at the scene.

The man arrested on suspicion of murder and was in hospital under police guard and being treated for minor injuries, a spokeswoman said.

Grover said he remained with the victim for about 30 to 40 minutesuntil the emergency services took over. He said he knew the man as a neighbour who would regularly walk by and say hello when they met.

A cordon remained in place around the street late on Saturday night, and police said inquiries were ongoing.