TAMPA, Fla. -- The man who leases the apartment where two men were shot to death -- allegedly by another roommate -- now faces federals charges in connection with explosives.

Brandon Russell faces federal charges of possession of a destructive device and unlawful storage of explosive material.

On Friday, the shooting suspect -- Devon Arthurs -- led police to the apartment where the bodies of two men were found, according to Tampa police. Officers also found Russell there, who had just returned from Army National Guard duty. He was crying, according to a federal criminal complaint, and was visibly upset.

Arthurs reportedly told investigators that the four men shared neo-Nazi beliefs until he converted to Islam, and that Russell had threatened to kill people and bomb infrastructure.

With a search warrant, police found a cooler with HMTD (hexamethylene triperoxide diamine), the complaint said. They also found potassium chlorate, potassium nitrate and ammonium nitrate. Also found were electric matches and empty 5.56-caliber casings with fuses.

They searched Russell's room and found Nazi/white supremacist propaganda, a framed photo of Timothy McVeigh, firearms and ammunition.

Russell admitted to making the HMTD, and said the chemicals were used to launch homemade rockets as part of his membership in an engineering club at the University of South Florida.

Arthurs, 18, 15350 Amberly Drive, has been charged with two counts of first-degree murder as well as armed kidnapping after he said he killed two men in the Hamptons Condominium, where he lived.

Police have identified the victims as Jeremy Himmelman, 22, and Andrew Oneschuk, 18. Both were living at 15350 Amberly Drive, Tampa, the same address as the defendant.

About 5:30 p.m. May 19, police were called to Green Planet Smoke Shop, 15325 Amberly Drive, where a possibly armed man was reported. Once there, they found Arthurs was armed. He had told two customers and an employee that they could not leave.

Police talked to Arthurs, and he agreed to let the hostages go and to surrender his weapon. He was taken into custody.

While officer interviewed him. Arthurs told them he had killed two people, and told them where the bodies were.