11/17/2014 02:48 EST | Updated 01/17/2015 05:59 EST

Vancouver hammer attack could have been fatal, police say

A 27-year-old man is in custody after two separate hammer attacks in Vancouver on Sunday night.

The first attack took place around 10.30 p.m. PT on the Seawall near Quebec Street at Terminal Avenue, when a stranger approached a 67-year-old man from behind and hit him in the head with a hammer.

The victim fell to the ground, and was struck again — in the head and on the arm — before the intervention of a passerby scared the suspect away.

Within half-an-hour, the suspect attacked another man at Main and East Hastings. The 49-year-old victim was hit in the head with a hammer, knocked to the ground and rendered unconscious.

Paramedics rushed him to hospital, where he remains in critical, but stable, condition.

Police said Monday the first attack could have been fatal if not for the witness stepping into help. The victim was treated for a broken arm and lacerations to the head.

The suspect — who was located a short time later — is known to police, who are now looking into his mental health history.

Police are recommending charges of two counts of aggravated assault.