OAKLAND (CBS SF) — A father and son were arrested on explosives charges early Tuesday after a California Highway Patrol traffic stop and an intense search of an East Bay hotel, authorities said.

The CHP said Jeremy Guy and his father, Ronald, both of Riverbank, Calif., were being held for having destructive devices and materials used to make destructive devices.

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The incident began with a CHP traffic stop of a Honda CRV at 4:45 a.m. Monday. Jeremy Guy failed to yield to a CHP officer’s request to pull over near Castro Valley and after a short pursuit, he was apprehended.

During a search of his vehicle, bomb making materials were discovered. The bomb squad was called and the material was safely removed.

Officers discovered Guy was staying at the Homewood Suites on the Embarcadero in Oakland and a search warrant was obtained and the University of California-Berkeley bomb squad alerted.

At around 7:05 p.m. Monday, law enforcement officers converged on the Homewood Suites, evacuating residents and blocking off several blocks around the hotel.

A search was conducted and Ronald Guy, who was found inside the hotel room, was taken into custody. The bomb squad searched the room and also another car associated with the pair.

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The father and son were reportedly storing destructive devices and home-made bomb making materials in the hotel room as well.

After the area was found to be safe, the CHP gave the all clear and allowed people to reenter the hotel and surroundings.

The investigation into what the two men were doing with the explosives is continuing.

“We need to look at why they are here and what they were attempting to do with the bomb-making materials found,” said Officer John Fransen with the CHP Golden Gate Division.

The investigation by the CHP and Oakland police was ongoing.

The CHP said they will release more details as soon as they can. They also issued asked people to remain vigilant when it comes to suspicious activity.

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“We plead with our public: call at 911 or 1-800-TELL-CHP, so we can look before it turns into a catastrophic disaster like we’ve seen over and over again in recent times in our country,” said Fransen.