Friday night an FBI agent confirmed to CBS 5 a search warrant was being served on the Coolidge home of a man taken into custody that afternoon, suspected of bombing a federal office with an IED 20 miles away.
They made entry just after 9 p.m. after securing the home and making sure it was safe to go inside.
The explosion violently shook the Social Security building on Marshall in downtown Casa Grande, but it didn't injure anyone Friday morning. The blast went off before the office opened for business.
Shortly after that bombing, the Feds descended on a neighborhood in Coolidge.
Residents of the Martin Valley development said Coolidge Police blocked off their neighborhood and kept them out of their homes all day. They were finally let back in to the neighborhood around 7 p.m. Friday.
Neighbors tell CBS 5 and property records confirm the home crawling with investigators, belongs to 47-year-old Abdullatif Aldosary.
"He's pretty quiet. He don't really come out of the house," said neighbor Miguel Pascual.
It was a scene other neighbors tell CBS 5 they had witnessed before. They asked not to be identified.
Court records show Aldosary served prison time in Safford four years ago for aggravated harassment against his then employer Hunter Contracting in Gilbert, and he is currently involved in an assault and disorderly conduct case in Casa Grande.
"I was pretty shocked about it. Around this little town, who knows to expect something like this," said Pascual.
The FBI said they're investigating the explosion in Casa Grande and are "utilizing all necessary resources" including: investigative personnel, the Evidence Response Team, Special Agent Bomb Technicians and the Hazardous Materials Response Team.
The blast was caused by a device that detonated at the rear of the building, according to Agustin Avalos of the city of Casa Grande.
It happened around 8:15 a.m. in a building that houses several other downtown businesses. All of them were evacuated, Avalos said.
"It was very scary. I'm still shaking inside. I never heard anything like that," said Alicia Perez, who works in the building.
No injuries were reported and the type of device had not been determined, Avalos said. But a source close to the investigation says it appears an accelerant and some type of plastic object was used in the blast.
"I don't know what would go through somebody's mind to do that," said Patty Rodriguez who works nearby.
Witnesses inside at the time said the explosion shook the building violently.
"I was afraid to go into the back because it was so close," said Perez.
The FBI is heading up the investigation, but officials from the Bureau of Alcohol, Tobacco, Firearms and Explosives, Homeland Security and Casa Grande Police Department are also investigating, Avalos said.
Aerial news footage over the bomb scene showed extensive damage to a doorway in the back of the building and to the side of an car near the doorway.
Casa Grande is about 50 miles south of Phoenix.
Stay with cbs5az.com and CBS 5 News as this story develops.
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