AFP reported on the evening of June 15 that an armed man was shot and seriously injured after trying to break into Little Rock Air Force Base.

An Air Force member at Little Rock base on guard duty. Photo: AP.

The suspect (whose name was not given) was hospitalized in critical condition and is under heavy guard, although his motive is still unclear.

A passerby was also taken to hospital for treatment and later discharged.

"The suspect was getting out of his vehicle and he had a weapon in his hand when the soldiers approached the suspect," base commander Colonel Charles Chip Brown told local media.

Mr. Brown said he could not determine whether the suspect fired any shots from the weapon in his hand.

Local officials said the Federal Bureau of Investigation (FBI) coordinated the investigation with the Little Rock Air Force Base Office of Special Investigations and local police.

However, according to Reuters, the FBI determined that the suspect acted alone and said there was no connection between the attack and terrorism.

The US military has been beefing up security at its bases since early May due to terrorism concerns. US authorities are concerned that Islamic militants will act on online calls from the self-proclaimed Islamic State (IS) to target US law enforcement and military personnel.

(According to AFP, AP/TTO)