Arnold Gate of the Anacostia-Bolling Joint Military Base in Washington, Wednesday, April 17, 2013.

Alex Brandon | AP

A lockdown on a US military base in Washington, DC was lifted Friday after authorities arrested a possibly armed person who entered the campus.

The all-clear came at 2:50 p.m., more than two hours after Joint Base Anacostia-Bolling alerted people that the person who was originally described as black with a medium stature and a Gucci bag was walking on the Base.

A base spokesman told CNBC that the suspect was arrested by grassroots security forces and will be transferred to the Metropolitan Police Department, whose officers are on site. The spokesman did not want to say whether the person surrendered voluntarily or was armed at the time of arrest.

A spokeswoman for the MPD had previously told CNBC that the department had received a call at 12:04 p.m. regarding the sound of gunfire at a location east of the base.

No victims were identified, said the spokeswoman.

MPD said they would only confirm that the person is male.

A base social media account first announced the potential threat at 12:37 p.m.

“LOCKDOWN LOCKDOWN LOCKDOWN” said a post on the base’s Facebook page.

“When you meet the person and have a safe path, RUN. If you don’t have a safe path, hide yourself. Prepare for the FIGHT, “reads the post.

An update later described the person as a black man of medium stature and “dreads that are medium-sized”. The person was wearing blue or green pants and a white tank top and may have been carrying a bag, according to this Facebook post.

This update, which came more than an hour after the lockdown was posted, advised people to “keep seeking shelter in the field”.

About 15 minutes earlier, the Facebook page had alerted people to be on the lookout for two people: a black man of medium build “with dreads” and “in ripped blue jeans” and the other a black man with green pants and a white top that “can be hurt”.

This was revised to only one person in subsequent posts.

Google Earth view of Anacostia-Bolling Air Force Base, DC.

Google Earth