The FBI is investigating why a retired Army sergeant walked into a Fort Bliss convenience store and shot two employees, one fatally, before he was gunned down by responding officers, the agency said Tuesday.

It was unclear whether Steven Kropf, 63, of El Paso, had any relationship with either victim, the FBI said in a statement. The agency described the Monday shooting at the West Texas Army post as an isolated incident and said it was investigating a possible motive.

FBI officials did not return calls to The Associated Press.

Authorities believe Kropf walked into the store about 3 p.m. and shot Bettina Maria Goins, who was pronounced dead at the military hospital, and another woman, who remained hospitalized Tuesday, the FBI said in its statement. Both women were civilian employees of the Army & Air Force Exchange Service, which runs merchandise operations for the military, including fast-food restaurants and convenience stores.

Goins, 44, worked at another Fort Bliss store and was at that particular convenience store to pick up more Halloween candy, her daughter told the El Paso Times. Maria-Laura Nasti said her mother was an innocent bystander.

"He took her away from us. It was senseless," Nasti said.

At a news conference Tuesday, post commander Maj. Gen. Dana Pittard said the post was safe.

"Fort Bliss is still, and remains still, one of the safest installations in the country," he said, adding that officials plan to "take a good look" at the private weapons policy at Fort Bliss.

The shooting came nearly 11 months after 13 people were killed in a shooting rampage at Fort Hood in central Texas near Killeen. Maj. Nidal Hasan, an Army psychiatrist, is charged with 13 counts of premeditated murder and 32 counts of attempted premeditated murder in the Nov. 5 shootings.

Hasan, 40, was paralyzed in the shooting and remains jailed. An Article 32 hearing — similar to a civilian grand jury proceeding — is scheduled for next month, when a military officer will hear testimony from victims and determine if there is enough evidence to warrant a trial.