Police are urging drivers to consider the conditions after four car crashes in two hours in Hamilton this morning.

In one crash a man collided head-on with a truck on Cobham Dr, Hamilton. He was trapped for a short period, but wasn't seriously injured.

Sergeant Phil Ruddell said other factors still needed to be ruled out, but a wet road had likely contributed to that crash, and others around the city.

Mr Ruddell said two people had been hospitalised from those, but neither seriously.

''It is more the inconvenience for all those people involved, and now their cars are off the road for an indeterminate period of time for what may have been a momentary lapse in concentration," he said.

''We are urging people to drive to the conditions, especially on these wet roads.''

- © Fairfax NZ News