Ishwar Singh, 50, was stabbed by Mannu after he enquired about the broken mirror of his car parked outside his house in Karol Bagh area of central Delhi around 8 a.m.
Ishwar Singh received several stab wounds in his abdomen and thighs and died before reaching a hospital. The attacker managed to escape.
Neighbours told police that Ishwar Singh had an altercation with Mannu earlier too. However, the reason of that fight is yet to be ascertained.
Police said they have launched a hunt to nab Mannu, who lives in another area.