Update 3:54pm: State Highway 2 has now reopened but Waka Kotahi NZTA says for travellers to expect delays.
"Due to a crash east of School Rd intersection, a lane is closed," says an NZTA spokesperson.
"Expect delays through this area and pass the scene with care."
Earlier 3:30pm: State Highway 2 is still closed following an earlier crash that seriously injured two people.
A SunLive reader says they were heading from Paeroa to Waihi/Katikati at 3.30pm and the Karangahake Road was still closed.
"Best to use Kaimais if heading to the BOP," they say.
Earlier: Emergency services are at the scene of a serious two-car crash on SH2 near the intersection of School Road, Karangahake.
Police were called to the scene at about 2.20pm.
A Police spokesperson says initial indications are that there have been serious injuries.
"The road will be closed and a diversion is in place, which will add significant travel time to anyone driving through the area.
"Motorists are advised to avoid the area and consider delaying travel, if possible."
At the scene? Phone 0800 SUNLIVE or email email@example.com