COLUMBUS, Ohio (WCMH) — The FBI confirms agents were “conducting court-authorized law enforcement activity” at an address linked to the man investigators say attacked the agency’s Cincinnati office Thursday.

Ricky Shiffer, 42, was killed in what authorities describe as a shootout with officers in Clinton County, following a chase and hours-long standoff after Shiffer fired a nail gun at the FBI office. The agency said Shiffer was also carrying an assault-style rifle.

According to records kept by the Ohio Secretary of State, Shiffer was registered to vote at an address on W. 3rd Ave. in Columbus’ Short North neighborhood.

Erin Bitzer and Chloe Merritt, who live in the apartment building, told NBC4 they were returning home from work Thursday evening around 5:00 when they saw the block had been cordoned off by law enforcement. The women said they were not allowed in the building, which had been evacuated.

Bitzer said they went to dinner and returned around 8:30. The scene was still active.

“They said that it would probably be even more — like a lot longer,” Merritt said.

The women said they spent the night at a friend’s home because they were unable to return. The yellow crime scene tape was gone Friday morning.

An FBI spokesperson would not provide any additional information Friday on the activity on 3rd Ave. or the investigation following Thursday’s incident in southwest Ohio.

“I’d like to know and be informed, at least,” Merritt said. “We just moved in here and the unknowns were a little bit scarier, I think, than anything else.”

The women said they did not know Schiffer, who is linked to other addresses in Ohio and Florida, according to public records.