Capitol police prepare for potential threat in D.C. after learning of militia group plot Capitol police in Washington D.C. are preparing for a threat on the Capitol building expected Thursday after receiving information of a potential plot by a militia group. The threat comes just two months after a mob stormed the Capitol on Jan. 6. and last updated 2021-03-03 23:18:28-05 (WXYZ) â Capitol police in Washington D.C. are preparing for a threat on the Capitol building expected Thursday after receiving information of a potential plot by a militia group. The threat comes just two months after a mob stormed the Capitol on Jan. 6.