PHOENIX (AP) -- A man charged with detonating a homemade explosive device outside a Social Security Administration office in Arizona had researched how to construct a particular explosive that authorities say has been used in terrorist bomb plots, according to a criminal complaint.
Abdullatif Ali Aldosary, 47, was charged in federal court with maliciously damaging federal property by means of explosives and being a felon in possession of a firearm. He appeared in a Phoenix courtroom Monday but didn't enter a plea. He is set to appear again on Wednesday.
No defense attorney was listed in court records, and a message left at Aldosary's home wasn't returned.
The small explosion occurred Friday morning outside a Social Security office in Casa Grande, about 50 miles south of Phoenix. Authorities said no employees were in the building at the time, no one was injured, and the damage wasn't extensive.
The federal Bureau of Alcohol, Tobacco, Firearms and Explosives initially opened an investigation but soon gave the case to the FBI. FBI spokesman Manuel Johnson declined to comment Monday.
According to the criminal complaint filed Saturday, authorities executing a search warrant at Aldosary's home in nearby Coolidge found documents explaining how to build a bomb hidden behind a picture. The papers included explanations of what specific chemicals to use, such as ammonium nitrate, the same type of fertilizer Timothy McVeigh used to blow up the Alfred P. Murrah Federal Building in Oklahoma City in 1995.
Handwritten notes found in the house read, "Materials Needed," according to the complaint.
Aldosary also sought information on how to create an explosive material known as RDX, "considered one of the most powerful of the military high explosives. RDX is believed to have been used in many bomb plots, including terrorist plots," the complaint read.
Authorities said they seized a handgun and rifle at the suspect's home along with hundreds of rounds of ammunition and several gallons of chemicals that could be used to make a bomb.
They tracked him down after witnesses reported his license plate on a vehicle seen fleeing the site of Friday's blast, according to the complaint.
Aldosary pleaded guilty in 2008 to felony aggravated harassment charges in Maricopa County, which encompasses Phoenix. He was sentenced to two months in jail and three years of probation, but his probation was revoked a year later and he was ordered to serve a year in prison.
A neighbor described Aldosary as friendly and cordial and said he couldn't believe the charges.
"I don't believe it, not for a minute," Swannee Welsh said. "If it turns out he did it I'll be the most shocked person in the world because I can't believe he would do anything like that. He was not an angry person."
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