An alleged operative for Al Qaeda imprisoned for 3 1/2 years as an enemy combatant is saying he was tortured and forcibly medicated with “a sort of truth serum” while in a Navy brig.

Jose Padilla, 35, was arrested in 2002 on suspicions that he was plotting a radioactive explosion, also known as a dirty bomb. He spent several years in a military jail in Charleston, S.C., without facing criminal charges. As legal wrangling over his fate continued, prosecutors in Miami charged him late last year with providing material support to a terrorist group and conspiring to murder, maim, and kidnap Americans abroad.

Lawyers for Padilla, who was born in Brooklyn and converted to Islam while in prison for gang-related crimes, made the claims of torture in a motion filed last week with a federal court in Florida.

“He was threatened with being cut with a knife and having alcohol poured on the wounds. He was also threatened with imminent execution,” the chief federal defender in Miami, Michael Caruso, wrote. “Additionally, Padilla was given drugs against his will, believed to be some form of lysergic acid diethylamide (LSD) or phencyclidine (PCP), to act as a sort of truth serum during his interrogations.”

Padilla’s attorneys argued that the alleged torture constitutes “outrageous government conduct” that requires that the criminal case against Padilla be dismissed. Judge Marcia Cooke has already dropped one of the charges against Padilla, but he could still be sentenced to life in prison on the other charges. The trial has been delayed until next January, at the earliest.

A top Al Qaeda leader, Khalid Sheikh Mohammed, reportedly admitted during interrogations that he tasked Padilla with locating radioactive materials and scouting out locations for a dirty bomb. However, the pending indictment against Padilla makes no mention of such a plot.

A spokesman for the Navy referred questions about Padilla’s treatment to the Justice Department. Prosecutors handling the case did not respond to calls seeking comment for this article.