One person has died after a serious crash in Otorohanga and another person has suffered critical injuries.

Fire and Emergency NZ said two crews were at the scene working to extricate two people trapped in the vehicles.

Police were called to the crash about 7.55am.

State Highway 3 is closed with diversions in place near Awatene Road and the Serious Crash Unit will attend the scene.

NZ Transport Agency said State Highway 3 is closed between Puketarata Rd and Kio Kio Station Rd.

A detour has been set up for eastbound traffic to turn left onto Kio Kio Station Rd, right onto Puketarata Rd, and left onto SH3. Westbound traffic is to do this in reverse.

8:15AM: Reports of a serious crash on #SH3 north of Otorohanga. Please follow directions of emergency services. Delays in the area are likely & road closure is possible. ^TP pic.twitter.com/t8vOXjIo2I

— NZTA Waikato/BoP (@NZTAWaiBoP) May 7, 2019

Motorists are advised to avoid the area.