Nine-term Rep. Jeff Fortenberry (R-Neb.) announced in a letter to supporters on Saturday that he plans to resign at the end of March following his felony conviction for lying to the FBI, CNN reported.

Nebraska Gov. Pete Ricketts (R) will call then call a special election to fill Fortenberry’s seat. Nebraska law requires that the election be held “within ninety days after the vacancy occurs.” State Sen. Mike Flood (R) was already challenging Fortenberry in the GOP primary and has been endorsed by Ricketts.

Fortenberry was found guilty on Thursday of lying to federal investigators about an illegal contribution made to his campaign by a foreign magnate. The Lincoln Journal Star reports that, according to federal prosecutors, Nigerian billionaire Gilbert Chagoury funneled “a bag of $30,000 cash” to “Los Angeles Dr. Eli Ayoub, who gave it to his relatives so they could write checks to Fortenberry at an LA fundraiser in 2016.” The jury found that Fortenberry lied when he told FBI agents he didn’t recognize Ayoub in photo.

Jurors convicted Fortenberry on three counts after less than three hours of deliberation. He faces up to five years in prison on each count, plus fines. Fortenberry’s sentencing is set for June 28.