Police have confirmed a climber in Canterbury's mountains became seriously injured after falling.

The Rescue Co-ordination Centre NZ say they received two locator beacon alerts just after noon from Arthur's Pass.

They sent helicopters from the West and East coasts of the South Island with ambulance confirming one person was flown to Christchurch Hospital in critical condition.

Police say a party of six people activated the locator beacons, after one member fell.