Updated

Federal officials on Monday remained silent on why they raided homes in Texas and Michigan this weekend that property records indicate are owned in part by a Houston art appraiser.

Dozens of agents, some wearing hazardous materials protective clothing, on Friday searched two homes in Houston and a condominium in Bryan, about 100 miles away. Agents on Friday, some donning protective clothing, also raided two properties in Michigan's Lower Peninsula: a home in the village of Suttons Bay and one in Leland Township.

Authorities in Houston on Saturday conducted two controlled detonations at one of the homes they raided. The FBI would not say was what detonated, only that it was a "potentially volatile substance."

Agents in Texas have finished their searches. IN an email Monday, FBI spokeswoman Shauna Dunlap said she could not comment on the case as search warrants related to the investigation remain sealed.

Sheriff Mike Borkovich in Leelanau County, Mich., told The Associated Press on Monday that although the searches involved hazardous materials, it was determined there was "absolutely no danger to anyone near the search sites or anywhere in Leelanau County." Borkovich said the FBI was still in the area Monday but would not discuss their activities or provide additional details.

Appraisal district records in Texas show the two Houston homes and the condominium in Bryan are owned either by Houston art appraiser Cecily E. Horton or by Horton and her husband, Andrew Schneck.

Leelanau County records show the home in Leland, Mich., and the one in Suttons Bay are owned by the Cecilia Earhart Horton Trust. Records list the mailing addresses for the Michigan houses as Horton's homes in Houston.

Messages left with Horton and her husband at their homes and businesses were not immediately returned Monday.

Horton is a partner at MKG Art Management, an art appraisal firm in Houston.