Update 2.45pm:

NZTA advise that due to a crash the road north of Apirana Rd is closed.

Police are at the scene of a serious crash on State Highway 30 near Horohoro.

"Please delay your journey or use an alternative route," says an NZTA spokesperson.

Alternative routes are as follows:

Northbound traffic: Right onto Whirinaki Valley Rd, left onto Waikaukau Rd, left onto Rehi Rd, left onto Corbett Rd, Left onto Tumunui Rd, left onto SH5.

Southbound traffic: Use SH5, right onto Tumunui Rd, right onto Corbett Rd, right onto Rehi Rd, right onto Waikaukau Rd, right onto Whirinaki Valley Rd, left onto SH30.

Update, 12noon: Police are at the scene of a serious crash on State Highway 30 near Horohoro.

Emergency services were alerted to a car that has rolled at the intersection of SH30 and Apirana Rd at around 10.40am.

One person is said to be critically injured.

Another person has minor injuries.

The Serious Crash Unit is on its way.

The road is closed. Motorists are advised to avoid the area or expect delays.

Earlier, 11.30am

There has been a serious vehicle collision on SH30.

The crash on SH30 between Rotorua and Kinleith was reported to emergency services at around 10.40am.

"Delays are possible," says an NZTA spokesperson.

"An update will be provided as soon as more information is available."

The crash is about 4.3km northeast of Waireka.