Residents of a lower Hamilton apartment building stopped suspected armed robbers in their tracks Monday after a resident of the building was robbed.

Hamilton police were called to the Chateau Royale condo building at 135 James St. S. just before 7 p.m. Investigators learned two masked men had knocked on the door of an apartment. The victim opened the door, thinking it was someone he knew.

The men, police say, forced their way in and tried to restrain the victim, who escaped, ran out and alerted other people.

Residents confronted the pair in the building, and there was a struggle. One suspect had a firearm, police say. The other had an "edged weapon believed to be a knife."

A maintenance worker in the building says one of the workers doing renovations helped stop the suspects, and was injured as a result. (Samantha Craggs/CBC)

People in the building detained the suspects until police arrived. Two of the people involved worked in the building, a maintenance worker said Tuesday.

The suspects had minor injuries and were taken to hospital. The victim and another resident were also taken to hospital for minor injuries.

"Detectives believe this was a targeted incident," police say.

The Chateau Royale building is next to the Hunter Street GO station. (Google)

A 33-year-old Hamilton man is charged with forcible confinement, robbery with intent to steal, wearing a disguise with intent to commit a crime, and the use of a firearm or imitation during an offence.

A 21-year-old Stoney Creek man is charged with assault with a weapon, forcible confinement, robbery with intent to steal and wearing a disguise with intent.

Anyone with more information should call police, or Crime Stoppers at 1-800-222-8477.