King County election officials found 150 more absentee ballots today that were mistakenly not counted in two previous vote counts but which are now expected to be included in the ongoing manual recount in the governor's race.

Added to 573 other ballots that were improperly rejected, up to 723 additional ballots may be counted in a county that has heavily favored Democrat Christine Gregoire over Republican Dino Rossi in this closest of close races.

Officials said they will attempt to learn the fate of 12 other ballots that weren't found this morning.

While observers from three political parties and a phalanx of television camera crews watched, election workers opened a locked cage in a warehouse and pulled out a cart containing trays of rejected absentee ballots.

Within minutes they found 150 of the ballots they were looking for in sealed envelopes in a tray with other rejected ballots. They were placed in a box, sealed, and taken to the King County Administration Building.

Elections Director Dean Logan said the ballots, like the other 573, were set aside because workers initially couldn't find voter signatures that corresponded to them.

TOM REESE / THE SEATTLE TIMES Republican observer Dan Brady questions vote counting procedures as King County Elections workers search for missing ballots this morning.

But unlike the other ballots, these apparently were left behind and forgotten. The original 573 votes were mistakenly identified as having mismatched signatures and then disqualified.

Logan called an emergency meeting with his staff last night after The Seattle Times asked election workers to check computer files on five absentee voters who were not on the original list of 573 rejected ballots.

Records indicated there was no signature on file for those voters and their votes had not been counted.

Logan said at the time that he thought the computer records were in error and that a search for the ballot envelopes would show the votes had been counted. But when election officials looked for the envelopes last night, Logan said, "They were not where they were expected to be."