Sturm Ruger & Co. knowingly allowed thousands of guns to be smuggled into Mexico — many used by drug cartels — resulting in the deaths of thousands of citizens, including mayors, police officers and bystanders, according to a suit filed by the nation’s government against Ruger, five other firearms manufacturers and a Massachusetts wholesaler.

The suit was filed in August in the U.S. District Court for Massachusetts, and Ruger, a gun manufacturer in Connecticut with a major production facility in Newport, disclosed it in a filing to the Securities and Exchange Commission.

Guns are practically illegal in Mexico, which has only one gun store and issues fewer than 50 permits per year, but criminals — many associated with drug cartels — have smuggled hundreds of thousands of guns into the country, causing political and economic havoc, alleges the suit.

The suit says some 340,000 of the guns come from the six defendant manufacturers, which also include Smith & Wesson Brands Inc., Barrett Firearms Manufacturing Inc., Beretta USA Corp., Colt’s Manufacturing and Glock Inc. Boston-based Century International Arms is named as a wholesaler to which Ruger “regularly makes substantial sales.”

The suit details numerous instances when the guns were trafficked. It also lists numerous crimes involving Ruger weapons.

The suit charges Ruger knew about the smuggling but allowed it anyway.

In response to the litigation, Ruger said in a Securities and Exchange Commission filing that “it is not probable and is unlikely that litigation, including punitive damage claims, will have a material adverse effect on the financial position of the company.”

— BOB SANDERS