Police are combing through a Chicago condo searching for clues in a double murder case that started more than 300 miles away.

Lincoln Park resident Michael McKee is expected in court tomorrow related to the killing of his ex-wife and her current husband inside their Columbus, Ohio, home.

A resident and former journalist said she started noticing signs on Saturday with a squad car parked outside, news cameras, and an officer on watch. On Sunday, the Ohio investigators arrived to collect evidence.

The search for evidence brought Ohio investigators to the top floor of a quiet Lincoln Park building, a corner apartment that was used by McKee, now accused of killing Monique and Spencer Tepe, his ex-wife and her current husband.

Police said they were found shot to death in their Columbus home late last month after Spencer, a popular dentist, did not show up for work.

There were no signs of forced entry. Police released a video asking for help before arresting McKee in Rockford, Illinois, linking him to a car seen on surveillance video around the murder scene.

"I said show me a picture, and I said oh my gosh, I know the guy, I talked to him at the pool," said long-time resident Gera-Lind Kolarik.

Kolarik shared the videos from inside her Lincoln Park building, where a Chicago police officer was seen standing guard at the front door just before Ohio investigators arrived — their truck parked in the garage.

"I just came from upstairs right now, and I had seen the police officers up there. They're going through the apartment right now. They had the door open. They were taking stuff out, putting stuff in boxes right now," she said.

Kolarik added that she first met McKee at the building's rooftop pool over the summer as he was using the grill.

"We just talked to each other. Was very pleasant, very nice man, and he had just moved in," she said.

The building management told condo owners and residents, "Due to an active police investigation involving a resident... they may see and encounter law enforcement officials in and around the building over the next few days."

Kolarik said the high-profile case may have caught the attention of people living here, though her final thoughts remain with the victims — the Tepes and their two young children, just 1 and 4 years old, found unharmed in the same home.

"As a journalist, we realize that these kids have to live their life now with what has happened and to create their lives," she said.

McKee is scheduled to appear in a Rockford courtroom on Monday at 1:30 p.m.

CBS News Chicago will continue to provide updates on air and online.