PHOENIX (AP) -- Arizona authorities on Tuesday were questioning the circumstances of an explosion that tore off part of a man's foot after determining the stories told by witnesses weren't true, and that the property where a munitions maker once tested bomb-making materials was supposed to be vacant.
Earlier Tuesday, authorities said Steven Scott Lane, 49, was believed to have stepped on an underground explosive device while helping two tenants move out of a rented home in the rural area on the outskirts of Phoenix.
Further investigation revealed the home was supposed to be vacant and had not been rented to anyone, Maricopa County Sheriff's Deputy Joaquin Enriquez said.
"Were they trespassing, and if they were, were they involved in any criminal activity?" Enriquez pondered.
In 1997, federal agents raided the same property and discovered enough explosives to support a small army. At the time, Charles Byers, a former munitions manufacturer, lived there. He later pleaded guilty in federal court to illegally possessing grenade fuses and manufacturing ammunition. He was sentenced to probation.
In 1999, a state task force declared the 120-acre ranch safe after removing thousands of pounds of chemical explosives, including materials to make grenades and booby traps.
The explosive that went off Monday was not buried in the ground, and appeared to be an improvised device, Enriquez said.
A bomb squad was expected to be sweeping the property for several days.
While authorities haven't ruled out the possibility that the device that injured Lane was left over from the cleanup, they now say it could be unrelated.
Lane remained hospitalized Tuesday after losing part of his left foot and suffering severe injuries to his right leg, Enriquez said.
He had not yet been questioned by detectives.
The two supposed tenants had previously told authorities and media that Lane was helping them move out of the house after they learned that the previous owner had done munitions testing on the property.
"Obviously, their stories have changed now," Enriquez said.
Associated Press writer Paul Davenport contributed to this story.
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