A St. Paul man pleaded guilty Friday to three counts of aggravated stalking.

Michael J. Mangan, 43, accepted a plea deal in Ramsey County District Court that dismissed eight other counts of stalking and terroristic threats that were originally filed against him last year. He was scheduled to go to trial on all 11 charges Monday.

Mangan was arrested on Oct. 4 during a traffic stop. Police found a loaded gun, “hundreds of rounds of ammunition,” a boot knife and a gun-cleaning kit in his car.

According to the complaint: Mangan plotted to kill his ex-wife, cobbled together a “hit list” of people he believed wronged him and drew diagrams of his ex-wife’s workplace and apartment building. He has four children with the woman, three of them minors who live with their mother.

A search of his home yielded sealed letters to 11 addresses or groups of addresses. Mangan’s girlfriend told police he had instructed her to send them once he was “gone,” the charges said.

Mangan’s sister and brother-in-law went to police because they feared him. Mangan told several people in his letters that he would see them in hell.

“Your mother did this,” he wrote in a letter to his children. “… I took the only action I had left in my power and that was to remove the problem.”

Mangan is scheduled to be sentenced July 3, and could face 2 ¾ years in prison.