Three In Custody After Man Allegedly Stabbed To Death

A young man is dead and at least three others are injured after a string of stabbings in Sydney.

The latest incident saw a 20-year-old man die at Westmead Hospital after he was found with a serious stab wound at Parramatta Station about 5.05am on Saturday, police say.

Three male teenagers, aged 16 and 17 and 19, remain in custody after being arrested in a nearby street.

Superintendent Julie Boon said the death is believed to be linked to an altercation at Prince Albert Park, which occurred about half an hour before the 20-year-old was found gravely injured.

"Police are looking into the relationship between the parties, whether they knew each other or not, at this stage that's unknown," she told reporters.

READ MORE: Young Couple Charged Over Stabbing At Woolworths

The death came hours after three alleged knife attacks in Sydney's west and lower north shore, with one man due to face court on multiple charges including attempted murder.

The 29-year-old is accused of approaching a 66-year-old man in Merrylands on Friday afternoon and demanding his keys before stabbing him in the chest and partially lacerating his ear.

Police allege the victim grabbed the knife as he tried to stab him a third time, causing a severe laceration to the older man's hand.

The 29-year-old was later arrested, but not before he allegedly stole a car at another address and may have attempted to rob an as-yet unidentified woman.

He's been charged with attempted murder, armed robbery with wounding, stealing a motor vehicle and malicious damage, and is scheduled to appear at Parramatta Bail Court on Saturday.

Featured Image: Getty Images.