After 25,000 National Guard troops gathered in Washington, D.C., to secure President Biden’s inauguration, an outbreak of coronavirus has been discovered among their ranks. More than 100 members of the guard have tested positive for COVID-19 so far, a source tells Politico, and many more are quarantining at hotels in the area after coming into contact with troops who tested positive.

The Senate Rules Committee is investigating coronavirus precautions taken by the National Guard amid growing concerns that troops were not tested upon their arrival in D.C., where social distancing was not always possible. Senators grew anxious after seeing photos of guard troops tightly packed together during breaks, including 5,000 guard troops who were reportedly stuffed into a garage with only one bathroom during their break.