CHRISTCHURCH, New Zealand - The jackhammers fell silent, church bells pealed and a Maori lament filled the air as New Zealand came to a standstill to mourn the estimated 240 people killed in an earthquake one week ago on Tuesday.

Flags were lowered to half-staff, and people gathered in groups in cities and towns to bow their heads for two minutes of silence at 12:51 pm local time, the moment when the quake struck Christchurch.

The hundreds of rescue and recovery workers in the shattered city of 350,000, who have been clambering over and through the wreckage nonstop since the quake struck, took a moment to pause and turn dusty faces to the sky or the ground. Friends and neighbors hugged each other. Traffic halted in the streets.

"I was born here, I've lived here all my life and I'll die here. It's my home, and it hurts so much to see it in this way," said Mike Cochrane, fighting back tears.

Cochrane had climbed out of his car at one of the city's busiest intersections to sit under a tree on a traffic island to observe the commemoration, climbing back in and driving off when a second peal of bells signaled the moment of silence was over.

Nearby, Rosie MacLean had left her realtor's office to stand in the street, a spontaneous act matched by thousands of others who also preferred to be outside.

"I suppose this is about hope, really, to realize we've got a future somewhere, but that's just hard to find at the moment," she said. "I guess this means we've reached a point where we can all acknowledge it together, which is a beautiful thing."

Prime Minister John Key had asked the nation's 4.5 million people to join in a show of unity for people "enduring tragedy beyond what most of us can imagine". And they did.

In the capital, Wellington, a traditional Maori lament rang out over the Parliament building.

Police said on Tuesday they have pulled 155 bodies from the wreckage, and said the number of others missing and feared dead indicated a final death toll higher than previously thought.

"The figure ... of around 240 is solidifying," Superintendent Dave Cliff told reporters.

The magnitude 6.3 quake struck within a few km of downtown Christchurch, when the southern city was bustling with workers, shoppers and tourists going about their activities. It brought down or badly damaged office towers, churches and thousands of homes across the city.

Key said a commission of inquiry would investigate the circumstances of the quake, including a detailed look at why the two worst-hit offices, where more than 100 people died - the Canterbury Television and Pyne Gould Guinness buildings - collapsed.

"We need to get answers about why those buildings failed, if there was something unique about them," Key told Australian Broadcasting Corp television.

He noted that both were built before substantial changes were made to New Zealand's building code in 1976.

The owners of the CTV building - where an unknown number of language school students from Japan, China and other countries are among the suspected 120 bodies entombed - said in a statement issued by their lawyers they would cooperate fully with the inquiry.

Lawyer Ken Jones said the owners had commissioned a detailed structural engineers report after an earlier quake on Sept 4, and that the report found superficial damage to the building from that temblor but raised no structural issues.

More than 900 international urban disaster specialists and hundreds more local officials have been picking through the wreckage.

No one has been pulled out alive since the day after the quake, and officials say it is almost certain no one else will be.

Associated Press