Story highlights Gen. Mark Milley: "There are gaps and failures on our part to report into the FBI"

On the percentage of cases upreported: "It's probably in the 10 to 20% of all cases."

(CNN) The chief of staff of the Army, Gen. Mark Milley, said Wednesday that the Army had made a "significant amount of omissions" following a review launched in the wake of revelations that Texas church shooter Devin Kelley's military criminal history was not properly relayed by the Air Force to the appropriate databases, which would have prevented Kelley from purchasing a firearm.

"There are gaps and failures on our part to report into the FBI; not just the FBI but other law enforcement agencies," Milley told reporters at the Pentagon.

"The data I saw, and again we are drilling into it to make sure it's accurate, we have a significant amount of omissions that concern the secretary and I, and it clearly tells us that we need to tighten up as well," Milley said.

"It's not just an Air Force problem, this is a problem across all the services where we have gaps in reporting criminal activity of people in service when they're convicted or they get a dishonorable discharge, those sorts of things, and getting that over to the appropriate law enforcement agencies," he added.

Milley said that in addition to bad conduct discharges like the one Kelley received, dishonorable discharges, which involve serious crimes and number about 150 cases per year, are required to be reported.

Read More