Winnipeg police are warning the public about the risks of buying from strangers online after several people were robbed at gunpoint after responding to online ads.

Police said a 21-year-old man found an ad online for an iPhone 5 and eventually agreed to meet the seller on Feb. 6.

The man went to the 300 block of Burrows Avenue around 8:30 p.m. to make the sale but it turned out the addresses were fake.

"It would be at that time that the suspect would approach them, in possession of a gun, and rob them of the money that had been brought initially to that location for the purpose of purchasing that phone," said Const. Jason Michalyshen with the Winnipeg police.

On Feb. 12, police got another call to the area of Burrows Avenue and Main Street where a 22-year-old man and 19-year-old woman were robbed at gunpoint.

The pair also set up a purchase of a smartphone with an online seller and agreed to meet him.

No one was injured in the robberies, and in both cases the suspect fled with cash.

Ray Giguere with Argy’s Collectibles said he does a lot of advertising online and often buys things off of the online site Kijiji.

“[I’ve] never had any kind of problems or even thought about having problems purchasing,” said Giguere.

He said he’s never been nervous about going to someone’s home to purchase something either.

Now, Winnipeg police are urging the public to be more cautious.

“You don’t know who you’re dealing with,” said Michalyshen.

“You are engaging in a type of activity that there’s a relatively high level of risk.”

Giguere said he was shocked by what had happened.

"I was flabbergasted somebody would go to such lengths -- the desperation some people have," said Giguere.

Support pages for the online site Kijiji recommend meeting a seller or buyer somewhere public, like a coffee shop.

Giguere said he thinks those messages should be attached to every ad.

Police believe the same man is behind both robberies, but they have not yet confirmed that fact.

The major crimes unit continues to investigate the robberies, and anyone with information is asked to contact police at 204-986-6219 or Crime Stoppers at 204-786-8477.