Seven people are in hospital after the four-wheel-drive SUV they were in flipped going round a bend in Christchurch early this morning.

A police spokeswoman said the accident happened shortly after 2am, near the intersection of Summit Rd and Dyers Pass Rd in Cashmere.

One person was in a critical condition and others sustained broken bones; all were taken to Christchurch Hospital by ambulance, she said.

The Serious Crash Unit is investigating.