Counter-terrorism expert explains how police will carry out manhuntpublished at 07:52 GMT

07:52 GMT

Todd McGhee wears a polo jumper and sits in his office during a Zoom callImage caption,

Todd McGhee said CCTV footage could help law enforcement to trace the shooter’s “direction of travel”

As a manhunt for the gunman continues, CCTV footage released by police shows the suspect walking out of the building after the attack. Neither his face nor a weapon are visible.

But Todd McGhee, a counter-terrorism and violent extremism expert, told BBC News that the video gives law enforcement officers “a direction of travel”.

“If you think of a bird’s eye view of a city block you’ll be able to then identify the next set of buildings with CCTV or Ring cameras – any type of information that law enforcement can pursue and continue on tracking the individual and the direction of their travel away from the shooting,” he said.

McGhee added that agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) on the scene would be looking to trace the type of firearm used, as well as its owner.

Investigators will also be looking for a “digital footprint” of social media posts or texts, and whether any vehicle was left behind that could help them to identify a suspect, he said.

CCTV shows a man dressed all in black walking down a streetImage source, Providence Police