State Highway 29 - the Kaimai Ranges - is closed after a truck's trailer rolled around 5.40am today, just west of Soldiers Road.
There are no injuries, says a police spokesperson.
"But the road is completely blocked until a crane can remove the trailer.
"Motorists are asked to delay their travel, and expect delays and diversions."
The highway is expected to be closed for the next few hours.
NZTA says an alternative route for westbound (Auckland) traffic is to use SH2 (via Paeroa). Westbound (Waikato) traffic is advised to use SH36/SH5/SH28 (via Rotorua). Eastbound traffic is advised to use SH28/SH5/SH36 (via Rotorua).
Police are also dealing with a second crash on SH29, between Hinuera (SH27 junction) and Te Poi (SH24 junction).
People are being asked to detour via Matamata (SH27 & SH24) - while the second has SH29 lanes blocked on the Kaimai Ranges summit.
"Please allow extra time for delays here with traffic management required. Temporary road closure on the Kaimai Ranges may be required to clear the truck later this morning."
At the scene?
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