STUTTGART, Germany -- Special agents from the U.S. Army Criminal Investigation Command are investigating the theft of guns and other military equipment from a base arms room in Stuttgart, military officials said.

The Army declined to say what kind or how many weapons were stolen or to identify the unit targeted, citing the active investigation. A possible breach of the base fence is also part of the ongoing probe "and something we are looking at very closely," said Ray Johnson, a spokesman for the Army's Installation Management Command-Europe.

A military official who was not authorized to speak to the media said that the site was Panzer Kaserne and that the theft included an unspecified number of guns. Panzer Kaserne is home to elite units such as Army Green Berets and Navy SEALs, as well as the garrison's headquarters and support units.

The break-in, which occurred earlier this month, comes at a time of heightened security concerns in Germany in the wake of a wave of high-profile terrorist attacks. These include the July 23 suicide bombing in Ansbach by a Syrian migrant who pledged allegiance to the Islamic State group and the July 19 attack by an Afghan refugee, also claiming allegiance to the group, on a group of tourists on a train in Wuerzburg.

On July 22, a German with dual German-Iranian citizenship killed nine people in a shooting rampage in Munich. While no Islamic terrorist link was established in that case, it has fueled a sense of angst in Germany, which has taken in about 1 million migrants in the past year.

The military did not say whether signs of the theft at the Stuttgart base pointed to an inside job or a security breach by an outsider.

"German authorities were notified and are working with the Army on the investigation," Johnson said. "Due to the ongoing investigation, we will not be releasing any additional information or any specifics on the items stolen at this time to protect the integrity of the investigative process."

Anyone with information about the theft is asked to contact the local CID office, the military police or the German police.