(Reuters) – A Florida man was sentenced by a U.S. judge on Tuesday to 25 years in prison for trying to blow up a synagogue in the state during a Jewish holiday last year, court officials said.

James Medina, 41, will first be treated at a U.S. prison medical facility for a brain cyst and mental illness before being moved into the general prison population, U.S. District Judge Robert Scola in Miami ruled.

The Federal Bureau of Investigation began watching Medina, who had converted to Islam, after he began expressing anti-Semitic views and a wish to attack a synagogue. They launched an investigation in late March 2016, court documents showed

Medina, who faced up to life in prison, had pleaded guilty in August 2017 to charges of an attempted use of a weapon of mass destruction and an attempted religious hate crime, court documents showed.

“This is a very, very serious offense,” Scola was quoted as saying in court by the Miami Herald.

Medina’s federal public defender, Hector Dopico, declined to comment when reached by Reuters on Tuesday afternoon.

Medina met with an FBI-affiliated confidential informant and explained his plan to attack a synagogue in Aventura, Florida, near Miami, the documents showed.

“Medina wanted to witness the explosion, hearing and feeling the blast from (a) nearby car,” the informant cited Medina as saying, according to the documents.

Asked why he wanted to do it, Medina said he wanted to kill Jews, adding: “It’s my call of duty.”

Medina was supplied with what he thought was an explosive device by federal law enforcement. The device was inert and posed no danger to the public, federal law enforcement said in court filings.

He was taken into custody as he approached the synagogue with the inert device and later admitted to his crimes, they said. No one was hurt.

(Reporting by Jon Herskovitz in Austin, Texas; editing by Bernadette Baum and Diane Craft)