Air New Zealand has added an extra plane to its services out of Christchurch, to meet the high demand from people wishing to leave the earthquake zone.
A shallow 6.3-magnitude quake struck at 12.51pm on Tuesday, 10km south-east of the central city, causing many deaths and widespread devastation.
Following a request from Civil Defence the airline has advised that a fourth wide-bodied aircraft has been brought in to operate services from Christchurch on Wednesday for tourist evacuees identified by Civil Defence.
Several extra services are being run, with Air New Zealand offering 996 additional seats on flights from Christchurch to Wellington and Auckland.
The airline will also run two extra Boeing 747-400 flights between Christchurch and Auckland from Thursday morning and is looking at further options to increase capacity.
Air New Zealand's special $50 fare for all flights to and from Christchurch will now run until midnight on Friday.
Domestic flights out of Christchurch resumed on Wednesday morning, and international flights resumed in the afternoon.
Airport chief executive Jim Bolt says that with airlines putting on extra flights he hopes the large backlog of passengers can be cleared by the end of Wednesday.
The airport was closed to all but emergency flights for the rest of Tuesday after the 12.51pm earthquake.
Tourists fly out
Hundreds of tourists who lost their passports and belongings in the earthquake were flown to Wellington by the Royal New Zealand Air Force on Wednesday afternoon.
Operation Airbridge ferried about 300 international tourists to the Capital, where various consulate and embassy staff met them.
Embassies will organise temporary passports so that the visitors can leave the country.
Many were unable to return to their hotel rooms after the quake and had to spend the night in temporary shelters.
Most have only the clothes they were wearing.