A 24-year-old man is guilty of trying to detonate what he believed was an explosives-laden van outside an Oklahoma City bank, a federal jury ruled Monday.

Jurors convicted Jerry Drake Varnell, of Sayre, of attempting to use an explosive device to damage a building and attempting to use a weapon of mass destruction.

Prosecutors alleged that Varnell planned to detonate what he thought was a half-ton (450-kilogram) vehicle bomb on Aug. 12, 2017. The FBI learned of the plan and an undercover agent posing as someone who could help construct the device provided inert materials.

Varnell had pleaded not guilty and his defense attorneys claimed he was entrapped. His parents testified that he is a paranoid schizophrenic who has been in several mental hospitals.

Testimony in the case began on Feb. 12 and included an informant who made recordings of his conversations with Varnell and an undercover FBI agent who helped Varnell build what he thought was a bomb. Authorities said the explosives were not live and the public was never in danger.

Federal investigators had been monitoring Varnell closely for months as the alleged bomb plot developed. They had received information that Varnell originally wanted to blow up the Federal Reserve Building in Washington, D.C., with a device similar to the one used in the 1995 bombing of the Oklahoma City federal building that killed 168 people.

During a 2017 meeting with undercover FBI agents, Varnell said he held "III% ideology" and wanted "to start the next revolution," a reference to the "Three Percenters" patriot movement — begun in 2008, galvanized by President Barack Obama's election — that has rallied against gun control efforts and pledges resistance to the federal government over the infringement of constitutional rights.

Prosecutors said Varnell will remain in custody until his sentencing, which will be scheduled in about 90 days. He faces up to life in prison for attempting to use a weapon of mass destruction and a maximum sentence of twenty years for attempting to use an explosive device.