Within seconds of Tuesday's quake, the Canterbury Television building in Christchurch, New Zealand, had become a tomb.

CHRISTCHURCH, N.Z. — Veteran television producer Rob Cope Williams was out in the field Tuesday, working on his weekly farm report, eating lunch at a countryside hotel, when he felt the jolt.

He and his crew figured it was a harmless aftershock from an earthquake that had struck five months ago.

“I said, ‘There’s another one. I’ll bet the (blokes) back at CTV didn’t even feel it,’ ” Williams recalled.

But they did. At 12:51 p.m., the ground beneath Christchurch shook violently, causing numerous downtown structures to collapse, including the one that housed Williams’ office.

The five-story Canterbury Television, or CTV, building on Madras Street, a city centerpiece for more than 40 years, shuddered and then crumbled down upon itself in the 6.3-magnitude quake. Within seconds, the home of a local TV station, a medical clinic and an English language school that drew students from around the world became a tomb.

Nobody knew that just then. During the next 36 hours, the CTV building — along with a handful of other urban towers — became the scene of numerous miraculous rescues; scores of people were pulled Houdini-like from the wreckage, calling for help in 10 different languages.

There was an injured woman who tapped on concrete to hasten help, the Christchurch resident who called her children on her cellphone to say goodbye, and the foreign student who texted her father in China to tell him she was trapped underneath rubble — all rescued.

But then the miracles ceased; the cellphones from within the carnage went silent. Two days after the quake struck, Christchurch officials said the CTV building would yield up no more life.

“Unsurvivable,” was the word they used.

For New Zealand, an isolated nation of 4.4 million residents, the earthquake’s statistics are heartbreaking. By Saturday, 123 people had been confirmed dead and more than 200 others listed as “missing and in concern.” More than half — about 120 — were believed to be buried under the smoking remains of the former social centerpiece on Madras Street.

Among those presumed dead are Murray Wood, managing director of Canterbury Television and the father of six children — five sons and a daughter — and Rhea Mae Sumalpong, 25, one of nine Filipino nurses believed to remain there.

There is also Maysoon Abbas, a Baghdad-trained family doctor who was seeing patients on the fourth-floor clinic when the quake struck, “helping people to the last moment of her life,” her daughter said.

And there is Donna Manning, a TV producer whose husband and two children suffered another blow after the one that nature delivered: While they sat outside the CTV building, awaiting word on her fate, burglars hit their home.

Then there are the estimated 40 foreign students at the King’s College language school, including a dozen from Japan; the Japanese government sent a specially trained search-and-rescue team that has concentrated on the CTV building.

A Japanese reporter assigned to cover the earthquake’s aftermath said the entire nation was awaiting word of the students’ fates.

Christchurch officials are grim about the immediate future of their beloved city, where the statue of founder John Robert Godley sprawls broken in pieces at the base of its plinth in a central square, a wound inflicted by the temblor now known in Christchurch as the Canterbury quake.

Rebuilding costs are estimated at $10 billion, and engineers say one-third of buildings in the central business district — most made from brick — will be demolished.

There are other tragic sites, such as the downtown Pyne Gould Guinness building where multiple bodies were recovered. And the iconic Christchurch Cathedral, where numerous people died when the spire collapsed, raining brick and mortar atop noon-hour visitors.

But the CTV building remains the most significant in its death toll; each day searchers pull more bodies from the wreckage.

TV producer Rob Cope Williams, 61, remains haunted by the loss of a dozen colleagues and the building he reported to for 21 years.

“I can still see their faces and hear their voices,” he said. “They won’t go away.”