Officials continue to investigate the cause of a fire in an Oakhill Avenue home Friday evening that injured four firefighters and caused more than $300,000 in damages to the house and its contents.

Fire Marshal Bob Pratt said the fire started at about 6:45 p.m. Friday in the roof on the first floor and spread to the attic and the second floor. There was water damage through the rest of the house, he said.

Roofing work was being done on the house earlier in the day and will be investigated as a possible cause of the fire, Pratt said. Further interviews will be done today to determine the cause of the fire.

Although two fires, one on M.A.C. Avenue and one on Grove Street, this summer were ruled to be arson, Pratt said Friday's fire did not appear to be connected.

The residents, a couple whose neighbors said lived in the home for 35 years, were uninjured. They declined to comment.

Three firefighters sustained non-life threatening burns and one was cut on the hand by falling glass, Pratt said. All four were treated and released from Lansing's Sparrow Hospital on Friday evening, he said.

Pratt said the structural nature of the house, which is nearly 100 years old and made of very tough materials, made fighting the fire very labor-intensive and required "more firefighters there than any residential fire" he's fought.

Crews were on-scene until after 11 p.m. Friday, more than four hours after the fire started.

The two neighboring houses, an owner-occupied house and Phoenix cooperative house, were evacuated Friday evening.

Ten of the 28 Phoenix residents were home at the time. They were told they could return to the co-op at about 10 p.m.

Carrie Nelsen, a social work junior and Phoenix resident, said she came home from work at about 8 p.m. to find the house evacuated. She said she waited with other residents until firefighters checked the house and let them back in.

"The house was really smoky, especially the rooms closest to that side," Nelsen said.

Phoenix co-op resident Rachel Jannazzo, a studio art senior, said Friday evening that she was in the living room and could smell smoke when she saw a fire truck and ambulance pull up.

"It didn't look that bad at first," she said. "It got worse."

Witnesses said smoke was visible from as far away as the Frandor area.

Jannazzo said police and firefighters told those at the co-op to evacuate, so she went through and knocked on doors to be sure everyone got out.

"Not a lot of people were home, luckily," Jannazzo said. "We were allowed to go back in at one point and were told we could get our valuables."

Jannazzo said she grabbed her guitar.

"It's all just possessions," she said. "Thankfully, everyone is OK."

She said the couple who lived in the home were tolerant of living next to students, and sad the situation was scary.