Five men have been arrested after last weekend’s fatal stabbing of a man in downtown Melbourne.

The men are in police custody as they are questioned over the attack which killed West Australian man Alier Riak, 23.

Mr Riak’s older brother, Kuol, 26, was also injured in the brawl which saw his brother knifed in Melbourne’s Docklands on Sunday, March 13.

Emergency services responded to the brawl at 3:20am, taking the two brothers to hospital where Alier died shortly after.

‘Senseless loss of life’

Victoria Police assistant commissioner Bob Hill said authorities had thrown significant resources at the investigation.

“I know the events of last weekend were incredibly distressing for many in our community,” Mr Hill said.

“We experienced the senseless loss of life.

“The victims of this incident were innocent parties who were good people: good students, good athletes and from a good family.”

A 19-year-old Derrimut man, a 21-year-old Wollert man and a 21-year-old Tarneit man are in custody after being arrested on Friday and facing Melbourne’s Magistrates’ Court overnight.

Police arrested a 22-year-old Taylors Hills man and a 20-year-old Epping man on Saturday morning.

Anyone who witnessed the incident or had information has been asked to come forward and speak to police or contact Crime Stoppers.

-AAP