PORTLAND, Maine — A transient with ties to Presque Isle appeared before a federal judge Wednesday accused of spitting in the face of a postal clerk earlier this month.

Derek P. Dow, 28, is charged with assault on a federal employee. He was arrested Tuesday.

Although Dow is homeless, according to court documents, his parents live in Presque Isle.

U.S. District Judge Nancy Torresen ordered that Dow be held without bail temporarily. He did not enter a plea. A date for a detention hearing has not been set.

The U.S. Attorney’s Office late Wednesday afternoon filed a motion asking Torresen to order Dow to undergo a psychiatric evaluation to determine if he is competent to understand the nature and consequences of the proceedings and to assist properly in his defense.

Dow allegedly became angry on Saturday, Dec. 10, when a clerk at the post office on Forest Avenue in Portland told Dow he could not pick up his mail until the next Monday, Dec. 12. Dow’s mail had been put on hold until Sunday, Dec. 11, according to the complaint.

“Dow appeared to become upset with [the clerk],” the complaint said. “Dow then spit at [the clerk], hitting him on his right ear, the base of his neck and the left side of his face. Dow then walked away from the counter and left the building.”

The incident was captured on video, according to the complaint.

Dow allegedly admitted spitting in the clerk’s face during a Dec. 12 interview with a postal inspector. Dow said that “the government, the Portland police department and the post office were all part of a conspiracy against him and the Micmac Tribe of Native Americans,” the complaint said.

If convicted, Dow faces up to a year in prison and a fine of up to $100,000.