Yesterday's fatal stabbing in a Ħamrun apartment appears to have been sparked by claims that a boy was mistreated by the victim, according to investigators.

Brandon Pace, 21, died when he was stabbed several times at the entrance of his apartment in Giovanni Barbara Street.

His alleged aggressor, Kurt Grech, who had a child with a woman who recently started dating the victim, told police that Mr Pace had been mistreating his infant son.

The argument started over the phone and Mr Grech then went to Mr Pace's home, accompanied by his parents and brother.

Grech suffered a chest wound in the ensuing brawl. His mother was also injured, They fled the scene after the murder but were arrested shortly after and hospitalised.

Pace died in his sister's arms in the presence of his girlfriend.

Both aggressor and victim had a history of convictions, with Pace also having been held in prison.

This was the fifth murder this year.