The Seattle Police Department’s civilian-run Office of Police Accountability says a sixth SPD officer is under investigation for being in Washington, D.C., on Jan. 6, the day a mob stormed the U.S. Capitol in a failed attempt to stop the certification of the election of President Joe Biden.

OPA Director Andrew Myerberg said four of the six officers have self-reported that they were in D.C. on Jan. 6, and they remain on duty while under investigation. The other two officers are on paid leave while under investigation because the department learned they were in D.C. that day via photos on social media.

At least five people died, including a Capitol Police officer, during the failed insurrection, which was driven by a call by President Donald Trump to “stop the steal,” the slogan used to describe the baseless claim that he won the November election, not Biden.

Seattle police said it does not violate policy for officers to participate in a political event on their own time, out of uniform. The investigation is to determine whether any of the officers engaged in illegal activities or otherwise violated department policies, according to a post Friday evening on the Seattle Police Department’s blotter.

After the first two officers were placed on leave and put under investigation, interim Chief Adrian Diaz said any officer who was in the Capitol on Jan. 6 had to self-report their actions or face termination. Diaz has said any officers directly involved in the insurrection will be terminated.