Seattlepi.com has the story:

A political action committee supporting Joe Mallahan's bid for mayor was fined $5,000 Friday by Seattle's election watchdog for failing to properly report more than $100,000 in contributions from city firefighters and conservative business interests.

Wayne Barnett, executive director of the Seattle Ethics and Elections Commission, said the charges against the Working for Seattle PAC were "the most serious" in his five years on the job.

"It is unparalleled," Barnett said at a commission hearing. "$100,000 was raised 21 days before the election and nobody knew about it until this week."