PHOENIX (AP) – Three weathered grenades have been found on the Arizona property where a man was wounded in an explosion last week as authorities continue to investigate whether the materials were left over from a cleanup operation in the 1990s on the same site where a munitions maker once tested bomb-making materials.

Steven Scott Lane, 49, lost a foot and suffered injuries to his face and eye on Oct. 4 in the rural area on the outskirts of Phoenix.

Two witnesses said Lane was helping them move out of a rented home on the property when he stepped on something that exploded.

Investigators have since said the site had not been rented to anyone and was supposed to be vacant.

Bomb technicians found three “very weathered” grenades on the property after an extensive sweep, Deputy Joaquin Enriquez said Wednesday.

An investigation remains ongoing.

In 1997, federal agents raided the same property and discovered thousands of pounds of explosives, including materials to make grenades and booby traps, mostly stored in a shed on the site.

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 an extensive cleanup.

While authorities haven’t ruled out the possibility that the device that injured Lane was left over from the cleanup, they say it could be unrelated, given the changing stories of the witnesses and the fact that they were not authorized to be on the property.

Dr. James Schamadan, who was appointed by then-Arizona Gov. Jane Hull to head a team overseeing the cleanup, said the explosion last week may have been caused by leftover materials.

Schamadan said federal authorities initially planned to blow up the hut instead of removing the explosives, but environmental concerns sidelined that option. In anticipation of the initial plan, however, Schamadan said authorities built a berm around it by bulldozing dirt from the property into large piles. Authorities have said the explosion last week occurred around the berm.

“Who knows what was in there?” Schamadan said Wednesday.

The berm was created, he said, before his team swept the property for remaining explosives.

Byers told KGTV in San Diego last week that he didn’t believe whatever injured Lane belonged to him. Enriquez said authorities were still awaiting results of tests to determine exactly what exploded and where it came from.

Messages left for the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, which assisted in the initial disposal of munitions on the site, have not been returned.

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