Washington ( CNN ) -- Under cover of darkness , two people wearing dark clothing and ski masks enter a fire truck while its crew is busy with a rescue . They grab keys to secure areas of Washington 's subway system and flee . And it all happens just blocks from the Pentagon . In a jittery post-9/11 world , it 's small wonder the incident has raised concerns . But Washington Metro officials and authorities in Arlington County , Virginia , attempted to tamp down fears the September 19 theft is terror related . They said the suspects stole numerous items from the truck , and likely did not target the keys . Moreover , the officials said they quickly took unspecified steps to secure the region 's transit system . The incident occurred just across an interstate from the Pentagon between 4 a.m. and 4:30 a.m. , while the crew tended to a patient . An on-board video-camera captured images of the thieves as they either approached or departed the truck , Arlington Police Department spokesman Dustin Sternbeck said . Both Sternbeck and Metro spokesman Dan Stessel said numerous items were lifted , including the Metro keys . Both declined to say how many keys were taken , or what the keys opened . The fire crew reported the theft promptly , Sternbeck said , and canine dogs were sent to the scene . Sternbeck said police have not released the video of the suspects , but might if detectives feel it would help the investigation .
Two thieves in masks strike while fire crew tends to rescue near Pentagon . Suspects make off with a number of items , including keys to secure areas of Metro . Episode raises concern in post 9/11 Washington , but officials believe theft is isolated . Video captured incident that occurred in past week ; no suspects identified .