Desperate hours in quake's aftermath

>>> now we switch to the disaster zone in new zealand where it's already thursday and chances of finding survivors in the rubble of that devastating earthquake are fading by the hour. the death toll is now more than 70. it will almost certainly climb, sadly, given the number of those believed to be trapped. our own george lewis is with us live from the city of christchurch tonight. george, good evening.

>> reporter: brian, it's a city of frayed nerves tonight. we've been feeling aftershocks all day long as the effort to rescue people trapped beneath the quake rubble continues around the clock. as they survey the damage, many people in christchurch compare their city to a war zone . search and rescue crews say they have cleared about 40% of the collapsed buildings here. they're still pulling people out of the rubble. rosalind chapman ducked under her desk when the quake hit. she was rescued 12 hours later. anne bodkin got out with barely a scratch after 25 hours, her rescuers braving aftershocks to save her.

>> in the midst of what is by and large one of the bleakest days in the story of our city, the sun came out at the same moment as they removed ann from that building.

>> reporter: in the television office building , authorities fear as many as 100 dead could be buried beneath the rubble. they have given up hope finding anyone else alive here.

>> i don't believe it. why this building?

>> reporter: 80% of christchurch is without water. people scrambling for emergency supplies. fema deputy director tim manning was in christchurch for a conference. a former firefighter, he joined in the rescue effort.

>> eventually came back over here to a pancaked building where we worked in the rubble for a while trying to retrieve some people calling for help.

>> reporter: this is the second big quake here within a five-month period. as was the case with new orleans after katrina, some are talking about leaving christchurch and not coming back. christchurch officials have two words for people who want to help out, send money. they have got plenty of blankets, plenty of clothing, what they need now is cold, hard cash. brian.

>> george lewis with the unbelievable situation in new zealand tonight. george, thanks.