An anti-Semitic, white supremacist group told the Anti-Defamation League that the gunman who killed at least 17 people at a school in Parkland, Florida, was associated with it.

Jordan Jereb, an alleged skinhead and representative for Republic of Florida, told the ADL that 19-year-old Nikolas Cruz had been “brought up” by a member of the organization.

Jereb also said that Cruz had participated in at least one of the group’s training exercises. The group, described as “alt-right” by the ADL, had not asked or wanted Cruz to do the school shooting, Jereb said.

On Wednesday, Cruz used a semiautomatic rifle in a shooting spree at Marjory Stoneman Douglas High School. Cruz, a former student at the school who was expelled, was in custody. At least five of the victims were Jewish.

Broward County Sheriff Scott Israel, who is Jewish, said Cruz’s social media posts painted “a very disturbing” picture, CNN reported. Mayor Beam Burr said Cruz “had been dealing with mental health issues.”

BREAKING: Spokesperson for white supremacist group Republic of Florida admitted to ADL that Nikolas Cruz, alleged perpetrator of deadly Parkland school shooting, was a member & trained with his group, which seeks to create a “white ethnostate.” More info: https://t.co/1Y8sGbP6Gv

— Jonathan Greenblatt (@JGreenblattADL) February 15, 2018

The ADL said it contacted a hotline for the Republic of Florida after self-described members of the group claimed Cruz as a member on 4chan, a web platform frequented by members of the far-right.

The Republic of Florida “borrows paramilitary concepts from the anti-government extremist militia movement (not itself a white supremacist movement),” according to the ADL, and wants to create a “white ethnostate” in Florida.