The civilian version of the Army’s new handgun is having problems firing when it shouldn’t.

In recent weeks, both the Dallas Police Department and the Stamford Police Department in Connecticut have suspended use of their issued Sig Sauer P320 sidearm, the civilian equivalent of the Army’s recently adopted XM17.

Both departments have cited “drop performance” problems, citing incidents when the weapon was dropped and then discharged itself.

The Army awarded a 10-year, $580 million contract to Sig earlier this year to produce its new handgun, the first replacement to the M9, made by Beretta for the Department of Defense, in more than three decades.

An officer in the Stamford department has filed a federal lawsuit after he claims that his holstered P320 fell, hit the ground in a parking lot while he was loading gear, and fired. The bullet struck him in the back of the leg and lodged near his kneecap, according to the lawsuit.

Sig Sauer issued a press release on Aug. 8, claiming that the firearm “meets requirements for industry and government safety standards.” Sig Sauer representatives noted that the company was performing voluntary upgrades to resolve “unintentional discharge” from dropping.

The Stamford officer’s lawsuit, filed Aug. 4, is seeking $6 million in damages and demands that Sig Sauer issue a recall and include a warning that the weapon is not “drop safe.”

The Sig release stated that the U.S. Army’s Modular Handgun System “is not affected by the voluntary upgrade.”

Sig has “developed a number of enhancements” to the P320 because of input from police, government and military customers, the release said.

It was not clear if the alleged “drop safety” issue that Sig claims is not present in the XM17 was resolved through military testing or by other means. Nor did the release specify the differences between the XM17 and the P320.

Army officials did not provide a response by press time. Sig representatives did not respond to requests for comment.