San Francisco police announced Thursday the arrest of two men suspected of possessing enough explosive material to level nearby neighborhoods.

Sean Patrick Gunther, 37, of San Pablo, and Marc Steven Ormando, 47, of Pacifica, were arrested March 6 after a separate undercover investigation in San Francisco led to their identification and alleged activities, police said.

The two were booked on multiple counts of unlawful possession of destructive devices.

After an investigation over many months with the cooperation of the FBI, U.S. Marshals Service and the Marin County Task Force, San Francisco police were able to secure search warrants to the suspects' homes, police Sgt. Danielle Newman said.

In Gunther's home, police said they found explosives and illegal narcotics. In Ormando's home, police said they found “a large cache of explosives, seventeen firearms, including handguns and rifles, and large barrels” of explosive-making chemicals.

“If something had gone wrong, it would have been catastrophic,” Newman said. “It would have leveled neighborhoods.”

Police allege the suspects not only had the materials in their possession but that they also manufactured explosives with the intent to sell and distribute.

The two were charged with 16 felony counts of possession, transportation or sale of destructive devices. Gunther was charged with an additional felony count of possession of methamphetamine, according to the District Attorney’s Office.

They pleaded not guilty to the charges Thursday, Assistant District Attorney Alex Bastian said.

Ormando’s bail was set at $2 million and Gunther’s was set at $1.5 million. At this time, the case will be handled by local prosecuting agencies, initially in San Francisco, but in the foreseeable future the case will be transferred to the San Mateo County District Attorney’s Office, Bastian said.

Bay Area NewsCrimeCrime & CourtsMarc Steven OrmandoPacificaSean Patrick Gunther

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