As per a Canadian police report, three cinemas in Toronto were attacked this week, prompting them to be evacuated.
Reportedly, masked men stormed into the theatres and sprayed an unknown substance.
One of the incidents happened around 9.20 pm on Tuesday at a cinema complex in Vaughan.
Several people in the audience started coughing after the two attackers, swearing masks and hoods, sprayed an "unknown, aerosol-based, irritating substance into the air" in a theatre, York Regional Police said in a statement.
Around 200 people were inside when a Hindi film was playing at the time. Meanwhile, similar incidents were held at Peel and Scarborough Town Centre theatres in Toronto City this week. "Coincidentally, they took place all within less than three hours on the same evening," a York police officer said on Wednesday.
"So we are certainly looking into the possibility that these incidents are linked," the police said.
Toronto police said officers got a call on Tuesday night about someone setting off a "stink bomb" in a theatre at Scarborough Town Centre.