LEWISTON, Maine (AP) — Maine’s congressional delegation is calling for the Army to investigate the events that lead up to the October mass shooting - the deadliest in the state’s history - by one of its reservists.

Robert Card killed 18 people in a bowling alley and a restaurant in Lewiston on Oct. 25, authorities said, and his body was found - with a self-inflicted gunshot wound - two days later. Reports soon began to emerge that the 40-year-old Card had spent two weeks in a psychiatric hospital and at roughly the same time was amassing weapons.

Members of the Maine delegation called for the Department of the Army Inspector General to investigate following a meeting with families affected by the killings in Washington.

The delegation said Friday that Army officials have informed them that there will be an administrative investigation into the events that preceded Card’s death. The members said in a statement that they have called for a separate, independent, concurrent investigation into the shootings that goes deeper than the administrative inquiry.

“This tragedy warrants a much broader, independent inquiry,” the delegation members said in the statement. “We must work to fully understand what happened - and what could have been done differently that might have prevented the Lewiston shooting - on the local, state, and federal levels. We must also give the American people confidence that the investigation is comprehensive and unbiased.”

Army officials did not immediately respond to a request for comment on Saturday.

The delegation’s call for an independent investigation came a day after members met with a survivor and family members of victims of the shootings. The families went to Capitol Hill to call for the Department of the Army Inspector General to find answers about how Card was able to own guns and commit the shootings.

Card’s access to military weapons had been restricted after he left the psychiatric hospital. Republican Sen. Susan Collins, a Republican and the senior member of the delegation, has said either New York’s red flag law or Maine’s yellow flag law could have been implemented to remove weapons from Card after the Army took action to restrict him. Collins, independent Sen. Angus King and Democratic Reps. Chellie Pingree and Jared Golden called for the investigation on Friday.

The Lewiston families said in a statement late Friday that they appreciated the swift action from the lawmakers after meeting with them. It’s imperative to determine “the facts surrounding the lead up to the October 25 mass shooting and to identifying any breakdowns or systems failures” that enabled Card to commit the shootings, the statement said.

“The joint letter makes clear that although the Army is currently conducting an administrative investigation, an inspector general investigation can happen concurrently,” the statement said.

An independent Maine commission is also investigating the shooting, and it has requested subpoena power to question the Army.