The revelation that the Capitol mob — covered in emblems of extremist groups — included off-duty law enforcement officers possibly assisted by working police is escalating pressure on sheriffs and police chiefs nationwide to root out staff with ties to white supremacist and far-right armed groups.

Law enforcement leaders have faced criticism in the past for failing to police their own officers’ involvement with extremist groups. However, the selfie photos that off-duty officers took inside the Capitol during the violent siege, which left one police officer dead and dozens of others injured, were a wake-up call for many who have long denied the extent of the problem within policing.

National Sheriffs’ Association President David Mahoney said many police leaders have treated officers with extremist beliefs as outliers and have underestimated the damage they can inflict on the profession and the nation.

Read more: Washington Post