FARGO (AP) - A man is accused of threatening North Dakota's congressional delegation in a dispute over taxes.

Ingmar Sjokvist, of Dazey, appeared Wednesday before a federal magistrate in Fargo on a charge of threatening to assault and murder Sens. Byron Dorgan and Kent Conrad and Rep. Earl Pomeroy, D-N.D.

Court documents say Sjokvist worked as a truck driver for a Fargo grain company, and that he called the offices of the North Dakota delegation in March or April, upset that the Internal Revenue Service was garnisheeing his wages.

In one phone call to Dorgan's Fargo office, authorities said, Sjokvist referred to Gordon Kahl, a tax protester involved in a 1983 shootout near Medina that left two federal marshals dead.

"You tell Dorgan and his buddies Pomeroy and Conrad that I'm gonna start with Dorgan's office and take them all down just like Gordon Kahl did," Sjokvist told a Dorgan staff member, according to court documents.

Earlier this month, Sjokvist called Dorgan's office, angry that no one had responded to a letter he had dropped off, according to an affidavit from agent Steven Demske of Federal Protective Service. "Sjokvist said he was so 'worried about the IRS that I'm bleeding … ,'" Demske said in his affidavit.

Later, Sjokvist told the Dorgan staff member, "You extend an invitation to Dorgan, Conrad, and Pomeroy that they're invited to a pig roast in Dazey, North Dakota, and you tell them they can bring their friends from the House and Senate and those special interest groups that they get all that money for because this is not my America, this is not what I went over and fought in Vietnam for."