Montreal police are investigating a murder that took place just after 8 p.m. Monday in the Saint-Laurent borough.

Police spokesperson Olivier Lapointe said a 40-year-old man was shot while standing on the first floor balcony of a seven-storey apartment building near the corner of Côte-Vertu Boulevard and Hocquart Street.

The victim was pronounced dead on the scene.

"We're trying to figure out, first of all, a motive for this murder. We know that the person was known to police, we're trying to explain that, but so far there is no clear motive and we're talking to possible witnesses to try to get a description of a suspect," said Lapointe.

Lapointe said police have made no arrests in the city's 31st murder of 2011, but investigators do have a theory.

"We can tell you that the crime or the situation could be related to organized crime," said Lapointe.

A photo taken Tuesday of the balcony where the victim was shot. (CBC/Elias Abboud)One witness who lives in the building said the victim was Lorenzo Lopresti. The list of tenants in the building's entrance includes the name Lopresti.

The witness told CBC he heard several gunshots, ran outside to the victim's ground floor balcony, and saw that the victim had been shot several times in the head and in the upper body. He said the victim appeared to have pulled a barbecue on top of himself.

One woman who was in the apartment at the time was taken to hospital to be treated for shock.