A few years ago, Arif Dewji, owner of House of Flags and Banners in Coquitlam, B.C., got an odd request from a prospective customer.

A man who seemed to be based in New York sent over the design of a flag he wanted printed.

At first Dewji did not know the meaning of the white logo set against a black backdrop, but something seemed fishy. After some online digging, he realized it was the flag used by followers of the Islamic State terror group.

"I didn't touch it with a dirty shirt," he said.

Edmonton police have said an Islamic State flag was found last weekend in a vehicle involved in what they are investigating as a terrorist attack.

Abdulahi Hasan Sharif, a 30-year-old Somali refugee, is accused of hitting a police officer with a speeding car, stabbing him and then mowing down pedestrians with a cube van. He faces 11 charges, including five counts of attempted murder. Sharif does not currently face any terrorism charges.

Dewji said he doubts anyone in Canada would have been able to get his hands on a professionally made flag locally, but it's possible it came from China. Images of the flag come up in search results on the Chinese e-commerce site Alibaba, but not on eBay or Amazon.

Dewji told the would-be client he wouldn't print his flag.

"Basically the conversation went dead and he just hung up the phone."

Edmonton flag shop refuses to print ISIS flags

Phyllis Bright, owner of The Flag Shop in Edmonton, said she had a similar inquiry this summer.

A man called asking for an Islamic State flag to be printed and, when she refused, he asked for a plain black one instead. Presumably he intended to stencil on the logo in white paint.

At first she didn't think much of it. Bright said she is sometimes sheepishly asked for Confederate flags, which are seen as a symbol of America's history of slavery, and she declines.

"The more I thought about it, the more fearful I became," Bright recalled.

"It really scared us because I think until last weekend we felt very sheltered in Edmonton and the fact that someone would even ask about it was very scary."

She did not have the man's name, but she tracked down his number, which was local. She called the RCMP, who referred her to the Edmonton police. She said the police told her there wasn't much they could do based on just a flag request, but that they'd keep the information on file.

Bright said she has no idea where someone could have picked up the flag found in Edmonton, but she added it looked professionally done in photos she saw in the news.

Until last weekend we felt very sheltered in Edmonton. - Phyllis Bright, owner of The Flag Shop

Both Dewji and Bright said their businesses refuse to sell flags emblazoned with symbols associated with hatred, such as Nazi swastikas, unless it's for a legitimate purpose such as a film or stage production.

The flag associated with the Islamic State is black with white Arabic writing along the top. Below that is a white circle with black writing that is meant to portray the seal of the prophet Muhammad. A flag with a similar design has been used by members of the Somali terror group al-Shabaab. Many jihadist groups use some variation of a black flag with white script, sometimes referred to as a "black standard."

The design has sown so much confusion and fear that when a Zurich man hung a black-and-white Jack Daniel's whiskey flag in his window, neighbours raised concerns, said a report in the U.K. tabloid The Sun.

Inscriptions on the Islamic State flag together make up a basic declaration of faith recited by Muslims around the world — that Allah is the only God and Muhammad is his prophet. Mainstream Muslims have been angered to see the message appropriated by the terror group in such a way.

Andre Gerolymatos with Simon Fraser University's terrorism, risk and security studies program likens using the flag to white supremacists using a Christian cross.

"It just shows that these people are trying to exploit peoples' sentiments and beliefs by perverting them."