10:05 PM: Thanks to the texter who asked about a stopped ferry off Alki. According to a tweet from the Bainbridge Island Fire Department, there was a report of a possible person overboard from the Bainbridge-bound M/V Puyallup. We note via MarineTraffic.com that Seattle fireboat Leschi is in the area too, and the Bremerton ferry M/V Kaleetan is stopped. The BIFD said the U.S. Coast Guard also would be responding.
10:11 PM UPDATE: Washington State Ferries has now acknowledged the “search and rescue operation” via its “bulletins” page.
10:29 PM UPDATE: Per BIFD, the Coast Guard is sending a helicopter to help.
10:42 PM UPDATE: Our partners at The Seattle Times quote the USCG as saying this started when a life ring with a strobe light was spotted in the water, and that a head count was being done aboard M/V Puyallup to try to determine if anyone is missing. It’s now headed back to Colman Dock.
11:31 PM UPDATE: The Coast Guard has tweeted that it’s still searching. Puyallup remains docked in Seattle, while Kaleetan headed back to Bremerton. (Added: Three minutes after this update, Puyallup left for Bainbridge.)