Several law enforcement agencies, including the Drug Enforcement Administration and Federal Bureau of Investigation, were investigating in East Haven on Thursday.
The investigation was on Tyler Street Extension, but the details on what it was about are limited.
Agents were investigating at the back of a businesses and they wore gas masks and handled boxes marked as evidence.
Business owners were shocked by the law enforcement presence.
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“It’s a pretty busy street, but this is crazy,” Randy Weidner, of East Haven, said. “We’re coming down this morning and there’s every cop car in the world down here.”
He said he didn’t know what was going on until he spoke with the landlord.
“I talked to the landlord and he said it was a fentanyl factory in the back, apparently,” Weidner said.
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The DEA has not confirmed the focus of the investigation.
Heavy machinery was seen inside the garage where the investigation was taking place. Machines were boxed up and taken away.