The sheriff's deputy's son who was arrested in a series of fires set at African American churches in Louisiana last spring pleaded guilty Monday to four federal criminal counts, reports CBSNews.

Holden Matthews, 22, admitted he set the fires to raise his profile as an aspiring "black metal" musician, the U.S. Attorney's Office said in a statement.

The statement from federal prosecutors said that Matthews pleaded guilty to three counts of intentional damage to religious property, a federal hate crime carrying a possible 20-year sentence per count. He also pleaded to one count of using fire to commit a felony, which has a possible 10-year sentence. He entered the pleas in federal court in Lafayette. Three churches were burned in a span of 10 days, beginning in late March 2019, in an area roughly 140 miles west of New Orleans in St. Landry Parish.

Matthews is white, and the destruction of the three historic black churches evoked memories of civil rights-era terrorism. But race is not mentioned as a factor in the charges. The indictment said the fires were set "because of the religious character" of the properties.

Fire investigators previously said they were eyeing Matthews' interest in "black metal," an extreme sub-genre of heavy metal music, as a possible motive. Matthews' social media shows is the lead singer for a band called Vodka Vultures. The black metal scene was associated with Christian church burnings in Norway in the 1990s, and a smaller subset of black metal bands espouse neo-Nazi beliefs.

"Matthews admitted to setting the fires because of the religious character of these buildings, in an effort to raise his profile as a black metal musician by copying similar crimes committed in Norway in the 1990s," the U.S. Attorney's statement said.

Read more at CBSNews.

(Photo - Louisiana State Fire Marshal)