The chief of Capitol Police and the head of security for the House of Representatives said on Tuesday they were working to root out police officers with extremist views who might pose ‘insider threats.’

House Sergeant at Arms William Walker told lawmakers his office had developed an ‘insider threat awareness program’ to identify danger at a time when members of Congress face an elevated number of threats.

Days after the nation marked the one-year anniversary of the violent assault on the U.S. Capitol, he and U.S. Capitol Police Chief Tom Manger appeared before a House Appropriations subcommittee to discuss security.

‘The goal is to have police officers trained as insider threat specialists so we recognize the signs and symptoms and indicators that someone’s allegiance has changed,’ said Walker.

He added that his office will brief the full plan to the Capitol Police Board in upcoming months.

Manger said during the hearing that they needed to start addressing the potential of extremist views among officers during the hiring process.

‘After you hire someone, you do need to ensure that you have the kind of checks that are necessary to make sure that there’s not something that has changed in terms of their background,’ he said.

The chief added: ‘Having really good in-depth investigations to determine if an officer is involved or engaged in some kind of activity that would lead to a question about their loyalty to our mission – that’s important as well to make sure that those investigations are done thoroughly and decisive actions taken on those cases.’

Background checks, polygraphs and social media investigations are all steps taken to ensure candidates are right for the job of USCP officer, Manger said.

Action to identify personnel with extremist views comes after investigations into dozens of police officers who were accused of assisting rioters on Jan. 6.

They ranged from posing for selfies with rioters to helping protesters with directions inside the building.

Manger estimated that at least 30 complaints were made against against Capitol Police officers.

On the same day as the hearing, a senior Justice Department official told lawmakers it was setting up a specialized unit to tackle domestic terrorism.

Assistant Attorney General Matthew Olsen said the number of FBI investigations into suspected domestic violent extremists has more than doubled since the spring of 2020.

‘We have seen a growing threat from those who are motivated by racial animus, as well as those who ascribe to extremist anti-government and anti-authority ideologies,’ he said.

The formulation of a new unit underscores the extent to which domestic violent extremism, which for years after the Sept. 11 attacks was overshadowed by the threat of international terrorism, has attracted urgent attention inside the federal government and at the White House.