HARRISBURG, Pa.—Police are investigating a July break-in at the Pennsylvania Democratic Party headquarters, but a spokesman says party officials are convinced it wasn't politically motivated.

"Based on everything that we saw in the immediate aftermath leads us to believe this was a run-of-the-mill burglary," party spokesman Mark Nicastre said Wednesday.

Two laptop computer and a camcorder were stolen from the eighth-floor office in downtown Harrisburg during the overnight hours between July 10 and July 11, according to a news release ( http://bit.ly/NZrAL8) issued by Harrisburg police.

Police say there was no sign of forced entry.

A message left for the detective who is investigating the case wasn't immediately returned.