More than 1,000 additional people could still face charges in connection with the Jan. 6, 2021 attack on the US Capitol, according to a letter to the DC federal court from the US attorney in Washington.The one-page letter, which was reviewed by Bloomberg News, was sent late last year to the chief judge and hasn’t been previously reported. It offers details on what Attorney General Merrick Garland has called “one of the largest, most complex, and most resource-intensive investigations in our history.”