Montreal police are investigating a series of vandalism incidents that occurred overnight at more than a dozen metro stations across the city.

The Montreal Transit Authority (STM) confirmed that at least 16 different stations were targeted. Doors, walls, and some bus stops at the stations were covered with pro-Palestinian stickers and some graffiti.

Many of the stickers stated: Genocide in Palestine and Canada is complicit, and some graffiti called for a ceasefire in the war between Israel and Hamas, as the number of destruction and casualties in Gaza continues to rise.

The Service de Police de la Ville de Montréal (SPVM) said it began receiving calls from passengers and residents around 5 a.m. on Tuesday, half an hour before the trains started operating.

Meanwhile, police spokeswoman Sabrina Gauthier said the SPVM hate crimes unit was initially tasked with leading the investigation this morning as a precautionary measure.

Gauthier said investigators wanted to ensure there were no messages inciting violence against a religious group due to the violence that occurred at Jewish institutions last week.

The case has now been transferred to the SPVM Metro division.

Also in a statement, STM condemned the vandalism and said its maintenance teams were deployed to remove the stickers and assist with cleaning on Tuesday morning.

Stations that were vandalized include:

Jean-Talon.

Villa Maria.

Sherbrooke.

Gare.

Mont-Royal.

Beaubien.

Édouard-Montpetit.

Frontenac.

Pie-IX.

Viau.

Fabre.

Université-de-Montréal.

Parc.

De Castelnau.

Acadie.

Préfontain.

The police said investigators will review surveillance camera footage from many stations.

This vandalism occurs at a time of rising tensions in Montreal regarding the ongoing conflict between Israel and Hamas in the Middle East.