A western New York man pleaded guilty Monday to making death threats against Rep. Ilhan Omar.

Patrick W. Carlineo Jr., 55, of Addison, New York, made the threats against the Minnesota congresswoman in March. He is facing charges of threatening to assault and murder a U.S. official and being a felon in possession of firearms.

Carlineo made threats via phone call to Omar’s offices on March 21 and was later arrested in April.

He is facing a maximum of 10 years in jail and fines of up to $250,000. Sentencing is set for Feb. 14, 2020.

“The First Amendment right to freedom of speech carries with it the responsibility that individuals not make threats to harm lawmakers simply because they may disagree with them,” James P. Kennedy Jr., attorney for the Western District of New York, said. “The Second Amendment right to bear arms carries with it the responsibility that individuals who desire to possess firearms not commit felony crimes.”

In the threatening calls, prosecutors said Carlineo referred to Omar as a “terrorist,” made reference to her Muslim faith, and said, “somebody ought to put a bullet in her skull.”

The defense argued that he never truly intended to harm Omar, one of the first two Muslim women ever elected to Congress.

Carlineo was previously convicted of criminal mischief in 1998, making it illegal for him to possess firearms.

Authorities found two shotguns, three rifles, a .45-caliber handgun, and a stockpile of ammunition at his home.

Ilhan Omar
In this photo, Omar arrives at an election night results party in Minneapolis, Minnesota, Nov.6, 2018. Getty Images/ Stephen Maturen