Waterview tunnel is now open southbound two hours after a multiple-vehicle crash injured five people.
Waka Kotahi advised motorists at 3.30pm that a crash was causing major traffic congestion on State Highway 20.
At 5.15pm the tunnel was re-opened, Waka Kotahi said.
A Hato Hone St John spokesperson said five people were injured and two ambulances and one manager responded to the incident.
“Our crews assessed five patients, two in a serious condition who were transported to Auckland City hospital, and three in a minor condition assessed at the scene,” the spokesperson said.