Four people were injured after falling 25 feet.
Harborview Medical Center officials said three men will be discharged. The 23-year-old man will be admitted to an intensive care unit. He is in serious, but stable condition.
Officials say the tunnel did not collapse. Click here for photos from the scene.
Five people were working on the project, but four were injured.
SFD reported a heavy rescue about 2 p.m. All four patients were pulled from tunnel accident shortly after 2:30 p.m.
WSDOT posted the following statement on its website:
<em>We are still gathering information, but Seattle Tunnel Partners has informed us that an incident has occurred on the SR 99 Tunnel Project job site in the north portal area. Safety is STP's and WSDOT's number one priority. Right now, their field crews are focusing on making sure the site is secured. Emergency services were notified immediately and arrived on site after the incident.</em>
<em>We will provide additional information as it becomes available. </em>
Officials told KIRO 7 that no one from WSDOT or Seattle Tunnel Partners will talk on Thursday about the accident.
Thursday's incident happened in a construction zone for what will eventually be an operations building at the north end of the tunnel project.
While the tunnel machine Bertha is stalled on the Seattle waterfront 1,000 feet into its 1.7 mile drive to South Lake Union.
Contractor Seattle Tunnel Partners accelerated work on both ends of the project to make up time lost during the tunneling stoppage.
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