SAN JOSE (KCBS) – A man has been arrested on suspicion of setting a five-alarm fire on Sunday in downtown San Jose, that destroyed the building that formerly housed KNTV.

Meanwhile, arson investigators used cadaver dogs to search for three people still not accounted for at the site of the fire at 645 Park Ave.

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55-year-old Stillman Pfeffer was scheduled to be arraigned Wednesday afternoon on charges of felony arson and first degree burglary.

San Jose Fire Department spokesman Capt. Cleo Doss said accelerant detection dogs were brought in to help with the investigation.

“They came in from Oroville, because we don’t have any accelerant dogs locally,” Doss said. “Using the heavy equipment to move some debris around, in order for the dogs to get in to a safe area where they can operate, they were able to pinpoint some areas where they believe the fire may have started.”

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The building was occupied by homeless squatters and there were reports of a possible missing person. But the fire department has not been able to confirm those reports and said crews are still working their way through the rubble.

“Cadaver dogs will go through the rest of the rubble [this afternoon]. We’ll also have some fire crews here with thermal imaging cameras, just to make sure that there aren’t any hot spots that the dogs will step over or step on, so they are not injured,” Doss said. “They’ll be doing a secondary check to make sure there isn’t anyone left inside the rubble.”

The fire was first reported at about 3:00 p.m. on April 13 at the building at the intersection of Park Avenue and Montgomery Street. It quickly grew to five alarms and was finally put out about three hours later.

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Over two dozen homeless people were living in the former TV station.