Philadelphia police and the FBI are excavating the land around the Olney home where investigators found weapons, hazardous chemicals and a drug grow operation last month.

The target of the dig is the pipes at the residence. Police would not disclose what they suspected to find in the pipes, saying simply that they were searching for "evidence." The city water department assisted with the excavation, which began Wednesday on the 400 block of West Chew Avenue.

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Law enforcement initially searched the house weeks earlier after linking it to a bizarre case in Center City. On the morning of June 19, a U.S. Park Police ranger approached a man who appeared to be threatening a woman inside his car. Eugene Horsch, 44, furnished false DEA credentials. His companion produced identification belonging to a missing woman, whom the Inquirer later identified as Blair Tonzelli. The ranger also found a switchblade and two firearms without serial numbers in the vehicle.

Further inquiry brought Philly police and the DEA to the Olney house, where they discovered another firearm and ammunition. The team also found evidence of a narcotics grow operation and hazardous chemicals in the basement. The FBI was called to the scene to evaluate these substances.

It is unclear what happened to Tonzelli, who vanished from Kensington in 2023. Subsequent reporting from the Inquirer linked the house to a second missing woman. Amy McHale, the ex-wife of Horsch's late father Raymond, was last seen at the home in 2016 before she disappeared. 

Horsch, who has been arrested numerous times over the past 20 years, was charged with multiple weapons and drug offenses. He is awaiting a preliminary hearing scheduled for August.

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