Three Democratic lawmakers said they are being investigated by federal prosecutors for participating in a video urging service members to refuse illegal orders.

Reps. Jason Crow, Chrissy Houlahan, and Maggie Goodlander said they were contacted by the U.S. attorney in Washington seeking interviews related to the video.

The November message, which included other Democratic lawmakers with military backgrounds, was released during debate over President Trump’s use of the National Guard.

Trump denounced the video as “seditious behavior” and called for those involved to be arrested, Fox News has reported.

The lawmakers have condemned the probe as political intimidation and say they will not be silenced.