SAN JOSE -- Search dogs on Thursday again sniffed around the rubble of the former KNTV building destroyed by a five-alarm fire but did not find any human remains.

Two specially trained dogs alerted handlers Wednesday afternoon of a possible hit in the charred remnants at Park Avenue and Montgomery Street, but it was not conclusive.

Fire Capt. Cleo Doss said two new dogs -- Kato, a male German Shepherd, and Piper, a female border collie -- repeated the process in an attempt to confirm the results.

But at the end of the day, the two specially trained dogs did not hone in on any human remains, according to the fire department. They did locate what appeared to be the remains of a small dog.

Thursday night, fire officials said they would not be returning to the site on Friday, and would turn it over to the city for cleanup.

"Based on what they found, there were no remains that can conclusively be called human," said fire Capt. Rob Brown. "There's not much more they can do."

If the dogs -- including one used in the aftermath of Hurricane Katrina and the Sept. 11 terrorist attacks -- detected something in the same area as the other dogs, crews were prepared to excavate. If remains were found, San Jose police would have been called in to take over.

Firefighters, fire investigators and heavy equipment stood by throughout the day.

On Wednesday, a homeless man was charged with using a liquid accelerant to burn down the building, which had most recently been a haven for the city's homeless.

Stillman Pfeffer, 55, of San Jose, was charged with arson and first-degree burglary.

Pfeffer was arraigned Wednesday and did not enter a plea. He is being held without bail.

More than 100 firefighters from San Jose, Santa Clara and Sunnyvale battled the fire, which broke out at 3 p.m. Sunday. It was brought under control about two hours later but not before the roof and sides of the building collapsed. Two firefighters suffered minor injuries. Damage was estimated at $4 million.

The building was once home to KNTV but had been vacant since 2004. In 2012, it was used for fire training and recently as many has 30 homeless people have stayed overnight there. Pfeffer was reportedly homeless himself but was not staying in that building. Pfeffer is on probation for petty theft and had three prior convictions, authorities said.

The building was purchased by the city of San Jose's Redevelopment Agency in 2008 during its efforts to buy land in the downtown area for a prospective baseball stadium in an attempt to bring the Oakland Athletics to the city.

Staff writer Eric Kurhi contributed to this report. Contact Mark Gomez at 408-920-5869. Follow him on Twitter @MarkMgomez.