PENACOOK - An overnight fire caused extensive damage in a three-story townhouse unit and left five people temporarily without a home, Concord fire officials said Sunday.

Battalion Chief Guy Newbery said the fire started in a bedroom on the top floor in an end unit at the Island Shore Estates condominium complex about midnight. All five residents were out of the building by the time firefighters arrived and there were no injuries.

Newbery said it took about 40 minutes to extinguish the flames. The damage was extensive but contained within the one unit, Newbery said.

The cause was ruled non-suspicious, but investigators were still trying to determined what actually started the fire, Newbery said.

The family members were staying with relatives and would be interviewed by investigators Sunday or Monday.