A criminal complaint made public on Tuesday laid out the U.S. government’s claims against Representative LaMonica McIver, depicting her as a ringleader who assaulted two federal agents as she tried to block the arrest of Newark’s mayor, Ras J. Baraka, outside a federal migrant detention facility.

Ms. McIver, a New Jersey Democrat, was charged with two counts of “assaulting, resisting and impeding certain officers or employees.” She has flatly rejected the government’s depiction of the events of May 9, when she and two other members of Congress went to the new detention center in Newark for an oversight visit, which they have the right to conduct under federal law.

Alina Habba, the interim U.S. attorney for the District of New Jersey, suggested in a statement announcing the charges late Monday that Ms. McIver had refused an offer to settle the criminal case, but offered no details.

Ms. McIver told CNN Monday night that the Justice Department “wanted me to admit to doing something that I did not do.”

“I came there to do my job and conduct an oversight visit. And they wanted me to say something differently,” said Ms. McIver, 38, who represents New Jersey’s 10th Congressional District, which includes most of Newark.