OAKLAND (CBS SF) — Undercover San Francisco narcotics officers teamed with Oakland police and firefighters on a Thursday afternoon drug and weapons bust at an East Oakland motel that required hazmat teams.

The bust happened around 1:30 p.m. Thursday at the Crown Lodge Motel on MacArthur Boulevard between 98th and 99th avenues.

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Chopper 5 was over the scene as authorities zeroed in on the motel.

Police made four arrests, recovered several firearms and seized multiple pounds of fentanyl.

Investigators said no one was exposed to the drugs, but hazmat crews were called in to test samples and ensure that the dangerous synthetic opioid was handled safely.

The area between 98th Ave and 99th Ave on MacArthur Blvd were shut down to traffic during the operation.

By around 3:30 p.m., SFPD narcotics officers had departed and all narcotics and paraphernalia had been removed.

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Oakland police remained on scene to secure the incident location and provide traffic support, fire officials said. Oakland Fire Department personnel stayed on scene until the the 3rd party vendor completed site cleanup.