A mystery that has plagued residents of a small Alberta town for weeks — vehicle key fobs that suddenly stopped working in a grocery store parking lot, leaving drivers unable to unlock or start their vehicles and setting off the alarms — has been solved.

The story caught fire on social media around the world after CBC News first reported earlier this week about the mystery in Carstairs, a town of over 4,000 people, about 60 kilometres north of Calgary.

It was the talk of the town, with people speculating the disabled fobs could be caused by anything from interference from a security system recently installed by the Westview Co-operative grocery store, a nearby Tim Hortons that opened just after Christmas, ongoing highway construction, a radio tower or the demolition of an old Rona hardware building.

"I have heard everything from magic ley lines, to aliens, to it's a Liberal conspiracy they are testing a weapon to prevent us from voting in the next election. Goofy shit," Carstairs resident Brian Ingwersen​ told CBC News after the initial story was published.

Laura Strate works at the nearby dollar store, where people popped in to buy batteries for the fobs (which didn't solve the problem). She told CBC News earlier in the week that some people in the town were scared to go to the store because they weren't sure if their cars would work.

Well, fear no more, Carstairs.

On Friday afternoon, the store posted an update on social media.

"This is the moment you all have been waiting for. We have an update on the fob interference that was occurring in and around our Carstairs Food Store," Westview Co-operative said in a Facebook post.

'We are very pleased,' store says

Stephen Kennedy, asset protection manager for the grocery store, told CBC News on Friday that the source was not on the store's property, as many had thought.

"Innovation, Science and Economic Development advised they had located the source, and it had been rectified," Kennedy said, of the federal department formerly known as Industry Canada.

"They didn't identify what is was or where it was, other than to say it was 'consumer.' They advised it was not in relation to Co-op property. It was not on our property, but it was in the vicinity or the area.

"We are very pleased — pleased for our team, pleased for our guests, pleased for the community," he said.

"After investigation it was determined that there was faulty consumer electronic equipment stuck in transmit mode in the area, which was causing the interference. We will continue to monitor; however, we do not anticipate any further issues moving forward."

Remote car starter the culprit

A spokesperson with Innovation, Science and Economic Development Canada had more details.

"In this case, it was determined that it was a remote car starter. It has since been deactivated and the interference has stopped," Hans Parmar said, in an emailed response to CBC News late Friday.

Store management says it's nice to have closure.

"There were a lot of different theories and potential reasons for the interference, so we are extremely glad to have figured out the source," the store said in its statement.

"We want to communicate that this was not the result of any intentional criminal activity, or any other activity that was speculated."

Kennedy said the efforts the store took to resolve the problem were worth it.

"I think it was the right thing to do. We are a cornerstone of the community, and our guests and our team were being greatly impacted. We owed it to our team and our guests to be a part of the solution."