BREMERTON, Wash. (AP) — A Seattle-bound Washington state ferry mistakenly loaded with 484 more passengers than it was rated to carry had to return to the dock and leave the overflow at the Bremerton ferry terminal late Friday afternoon as Seattle Seahawks fans tried to reach an evening preseason game.

Ferry staff apparently thought the Cathlamet could carry 1,600 passengers when its capacity is 1,200, Washington State Ferries spokeswoman Marta Coursey said. In all, 1,684 passengers were loaded, so 484 had to leave, she said.

Coursey said she couldn't explain the "misjudged capacity," saying the Cathlamet has been on the route all summer.

The captain turned back after getting the total number of those on board, she said.

Washington state Transportation Secretary Lynn Peterson apologized to the inconvenienced passengers, promising a thorough review and adding that "everyone in the chain of command at Washington State Ferries responsible for this oversight will be held accountable."

When the captain's call for volunteers netted only about 100 passengers, state troopers were asked to assist, the Kitsap Sun reported (http://is.gd/iNCyuC).

A trooper found Chaz Forsberg, 27, of Silverdale, in the Cathlamet's men's room and told him he had to return to the terminal. "He said if I had a problem with it, I should send a complaint to the ferry system," Forsberg told the newspaper.

Troopers told passengers the boat would not sail until it was no longer overloaded, State Patrol Sgt. Tina Martin said. There were no arrests, and "nobody had to be physically removed," she said.

The Cathlamet left Bremerton about an hour late, Coursey said. She said she thinks everyone left behind was able to board the next Bremerton-Seattle ferry.

Those taken off the boat were given vouchers for a free trip, the spokeswoman said.

The ferry system added an extra late-night round trip on the route Friday night, Coursey said.

Washington State Ferries also said it was waiving the charge for vehicles and foot passengers from Seattle to Bremerton on four departures late Friday night and early Saturday.