Calgary police are investigating a Sunday morning altercation in the downtown core which left four men suffering from stab wounds.

According to police, a fight involving as many as 16 people occurred shortly after 2:00 a.m outside of a bar in the 200 block of 8 Ave. S.W. The fistfight escalated and four men were stabbed.

EMS, CFD and CPS members responded to the scene. The stabbing victims were transported by ambulance to Foothills Hospital. According to EMS officials, the most severely injured patient was considered to be in critical, potentially life threatening condition.

A man identified as a ‘person of interest’ in connection to the attack remains in CPS custody. Police continue to interview the man. Charges have not been laid in connection to the attack.

A number of witnesses were transported to CPS headquarters.

Investigators are reviewing surveillance video to identify the responsible parties.

Anyone with information about the stabbings is asked to contact the Calgary Police Service, 403-266-1234, or Crime Stoppers.