[Updated at 8:15 p.m. ET] Officials at a U.S. Air Force Base in southern Arizona have called off their response to a security situation that prompted a base-wide lock down, the Air Force said Friday in a statement.
The release notes that "increased security measures were taken around the base following the unconfirmed sighting of a man entering an office building, apparently armed."
No further information was provided on the situation or the person, whom the release characterized as a "suspect." But the Air Force did state that its officials have "terminated" their response to the incident.
[Updated at 6:57 p.m. ET] A gunman is holed up in a building on a U.S. Air Force base in Tucson, Arizona, a U.S. military official said.
No shots have been fired and law enforcement teams are on site, said the official, who has direct knowledge of the situation from conversations with base officials but did not want to be identified.
[Initial post, 3:45 p.m. ET] Arizona's Davis-Monthan Air Force Base was placed on lockdown Friday morning after an unconfirmed report of a someone suspicious with a weapon, Tech Sgt. Russ Martin told reporters.[cnn-video url="http://www.cnn.com/video/?/video/bestoftv/2011/09/16/az-air-base-lock-down.cnn"%5D
No shots have been fired, and nobody is hurt, said a different base representative, Staff Sgt. Caitlyn Jones.
Two schools on the base in Tucson, including Borman Elementary School, also were locked down. Perimeter and classroom doors were locked, and students are staying where they are, said Karen Bynum, executive assistant to Superintendent John Pedicone.
Base representatives said the report was being investigated, and that the reportedly suspicious person has not been located.FULL STORY