A serious crash involving four vehicles this morning closed the southbound land of State Highway 1 between Warkworth and Puhoi, north of Auckland.
Police said one patient was taken to hospital via helicopter in a serious condition, while two other injured people are receiving medical treatment at Northshore Hospital.
The crash happened at about 5.50am today.
The southbound lane of SH1 was blocked by the crash for about three hours, but has now reopened.
The Serious Crash Unit will be investigating.