The family of a man accused of attempting to detonate what he believed was an explosives-laden van outside an Oklahoma bank says he is a paranoid schizophrenic and that the FBI knew it.

Clifford and Melonie Varnell, of Sayre, Oklahoma, issued a statement late Tuesday that questions the tactics undercover FBI agents used to arrest 23-year-old Jerry Drake Varnell. He was taken into custody early Saturday for the alleged plot to detonate a vehicle bomb in an alley adjacent to BancFirst in downtown Oklahoma City.

Varnell, who lives with his mother and stepfather in Sayre, about 130 miles (209 kilometers) west of Oklahoma City, is jobless due to his schizophrenia and does not have the resources to carry out such an act alone, according to the family's statement.

"The FBI came and picked him up from our home, they gave him a vehicle, gave him a fake bomb, and every means to make this happen," the statement said, adding that authorities "should not have aided and abetted a paranoid schizophrenic to commit this act."

FBI spokeswoman Jessica Rice in Oklahoma City and Assistant U.S. Attorney Scott Williams declined comment Wednesday.

A federal detention hearing for Varnell is scheduled on Aug. 22. If convicted of attempting to use explosives to destroy a building in interstate commerce, Varnell could receive five to 20 years in prison.

His court-appointed defense attorney, Terri Coulter of Oklahoma City, declined comment.

Varnell "has suffered through countless serious full-blown schizophrenic delusional episodes and he has been put in numerous mental hospitals since he was 16 years old," the family's statement said. It added that his parents are his legal guardians and do all they can "to keep him safe and functional."

"The mental health system has consistently failed us due to the lack of establishments and health care coverage for a person like him," the statement said. Varnell takes medication "but he will never be completely functional in life," it said.

The Varnells say their son is easily influenced and they believe a confidential informant who tipped FBI agents off to the alleged plot may have helped inspire it.