The case of four homeless men in Thompson, Man., who were hospitalized after drinking an unknown liquid is not a sign that the city's homeless population is being intentionally targeted, RCMP said Friday.

Each man became ill after drinking an unidentified substance in a liquor bottle earlier this week. The bottle of clear fluid was found in a hotel room by one of the men, who then shared it with a group of friends.

Three of the men were taken to hospital immediately, while a fourth was later tracked down and given medical attention. All of the men who were treated in hospital have since been released.

"This little clear Alberta Springs vodka bottle was basically empty by the time I got to it, but I smelled it and it definitely smelled like paint thinner," said Davina Maier, spokeswoman for the city's homeless shelter.

"They had definitely ingested a solvent and not alcohol. I witnessed one having chest pains and the other having trouble breathing."

Maier said three bottles containing a similar liquid have been found in the northern Manitoba city, leading her to conclude that someone is targeting the city's homeless population.

"These bottles are being, like, placed around the downtown area," she said.

Police said that reports of bottles of solvents being left lying around for homeless people, however, are just rumours and that this was an isolated incident.

They say there is no reason to believe anybody is targeting homeless people in that community.

Nonetheless, officials have posted signs warning people about the danger. RCMP said they are investigating.

Excessive drinking is a widely acknowledged issue in the city of 13,000, located about 650 kilometres north of Winnipeg.

Earlier this year, the Manitoba Liquor Control Commission introduced restrictions on the amount of liquor customers can buy in Thompson in an attempt to control excessive drinking and bootlegging.

The problem is so bad, the Thompson Chamber of Commerce has in the past organized annual spring sherry-bottle collection drives to deal with the mess left behind by drinkers. In a typical drive, citizens picked up and returned 16,000 bottles for the five-cent-per-bottle refund.