Lee Boyd Malvo, who was sentenced to life in prison for his role in the sniper attacks that terrorized the Washington, D.C. area, said during an interview with actor William Shatner set to air Thursday that he and accomplice John Muhammad had recruited more co-conspirators to take part in the 2002 killing spree.

During a phone interview from prison to air on cable channel A&E, Malvo told Shatner he initially trained with three other snipers under the guidance of Muhammad. Two of them were murdered after being unwilling to follow through with the plan to wreak havoc on the entire Eastern Seaboard using silenced rifles.

The whereabouts of the third accomplice are unknown.

Dr. Neil Blumberg, Malvo’s psychiatrist, added that Muhammad threatened to kill Malvo if he backed out of the plan.

Police in the D.C. area are not convinced by Malvo’s confessions.

“I think Malvo’s full of crap,” the Washington Post quoted Fairfax County Homicide Detective Lt. Bruce Guth as saying. “He’s changed his story at least five or six times,” Guth continued.

Together, Muhammad and Malvo killed at least 10 people.

In the interview with Shatner, Malvo admitted his involvement in 42 other shootings.

The special will also reveal previously unseen footage of Malvo’s confession to Virginia police in 2002, Malvo’s father pleading for his son and a confession to Tuscon, Ariz., police about several murders that were not initially connected to the D.C.-area case.

Muhammad was executed last year in Virginia.