Crime has decreased in recent years in Montreal's metro system, with the exception of sexually-related crimes.

The Montreal police force reports there have been 26 crimes of a sexual nature in the metro system so far this year. That includes two cases of sexual assault, about six cases of exhibitionism, and about 15 cases of groping.

In the most recent case, a man used his smartphone to capture images under a woman's skirt.

Police say they have arrested nine suspects, thanks in part to surveillance camera footage of the incidents.

One man is facing charges of touching at least five women, with his alleged crimes taking place on the Orange line between the Henri Bourassa and Berri UQAM stations.

Over the past nine years sexual crimes dropped to a low point of 13 in 2013, and hit a peak in 2010 with 34. Last year there were 31.

Police say they take these kinds of crimes seriously and video from surveillance cameras can help identify suspects.

“It's a major crime. The aggression against women, you can't let it pass like that. You have to make a big investigation. We have police officers working with the STM,” said Insp. Roger Belair of the Montreal police metro division.

Overall crime against people has dropped 42 per cent since 2008.

“The overall crime rate is still going down, for about maybe 10 years,” said Belair.

Assaults have dropped from 299 in 2009 to 166 last year. There were many fewer robberies, with 129 robberies in 2014, compared to 177 in 2009.

Thefts have dropped slightly, from 341 to 311 over the same time frame.

2009 in when Montreal police officers began increased patrols of the metro system, replacing the STM officers that had previously been responsible.