CNN) -- Almost 200 rescue workers were sifting through rubble in search of survivors of a fireworks factory explosion that killed at least two people Thursday near Brazil's largest city, a city official said.
Civil Defense authorities put the toll at two dead -- one man and one woman -- and three missing. The fire department earlier said three people had been killed.
At least 12 people were injured and have been taken to hospitals, officials said.
The fireworks factory exploded at 12:30 p.m. (11:30 a.m. ET), in a residential area in the industrial hub of Santo Andre, on the outskirts of Sao Paulo, Santo Andre spokesman Alexander Soares told CNN.
Firefighters believe people were under the rubble, Sgt. Cordiero of the Santo Andre fire department told CNN. He declined to give his first name.
The workers were sifting through debris with shovels and at least two pieces of large earth-moving equipment, television pictures from the scene showed.
Sniffer dogs were also on the scene, Cordiero said.
The blast appeared to have destroyed a large section of the building, scattering debris onto surrounding streets. Nearby cars and houses were destroyed, civil defense authorities said in a news release.
Four city blocks have been cordoned off as rescuers conduct their search, they said.
--CNN's Helena DeMoura and Belen Lopez contributed to this report.
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