VANCOUVER -- Mountain Equipment Co-op says it's asking tough some questions about its supply chain after consumers on social media connected some of the brands sold at its stores to a major U.S. ammunition and gun manufacturer.

"We're gathering facts, listening to our members and figuring out the best path forward for our co-op," the Vancouver-based company said in a tweet Monday.

"MEC is committed to responsible supply chain practices and transparency and we will continue to be guided by those values."

The tweet came after MEC said its senior management would meet first thing Monday to discuss calls it stop selling Vista Outdoor Inc.-owned brands, including Giro, Camelbak and Blackburn. Utah-based Vista also designs, develops and manufactures ammunition, long guns and related equipment, according to its website.

Vista owns Savage Arms, which sells multiple semi-automatic rifles. Those are similar to the type of rifle a shooter used earlier this month to kill 17 people at a Parkland, Fla., school.

While MEC doesn't sell firearms, it does stock the helmets, sunglasses and other outdoor goods Vista makes.

A Change.org petition calls on the retailer to stop carrying the brands.

"Given the recent massacre of high school students in Parkland, Fla., MEC is facing an urgent ethical obligation: to act in accordance with its 'mission and values,"' the petition, which has been signed by about 900 people as of Monday late afternoon, reads.

Some people aired their concerns to the company on its Twitter and Facebook pages, asking it to stop selling Vista-owned brands.

Neither MEC nor Vista immediately responded to a request for comment. However, MEC answered posts on its social media pages, telling visitors their comments have been passed on to the company's management.

The company's mission and values include seeking "to motivate other individuals and organizations to act for people and the planet."

The company encouraged consumers to keep sharing their views via social media and promised another update by 5 p.m. PT.