MEXICO CITY >> Five days after the deadly magnitude 7.1 earthquake, the hulking wreckage of what used to be a seven-story office building is essentially the last hope: one of just two sites left where searchers believe they may still find someone trapped alive in Mexico City.

Among the families of the missing, there are periodic moments when spirits lift. A flurry of activity, or relatives are summoned to the search site, raising hopes that someone has been found.

But despair deepens when the work slows or even stops, when rain or an aftershock threatens the stability of the tottering pile, and as day after day passes without their loved ones emerging.

For the family of Adrian Moreno, one of the missing, the emotional roller coaster is getting to be too much. Moreno’s mother has a look of anguish and has largely stopped being able to speak. His boyfriend, Dario Hernandez, looks lost, his gaze tear-stained and unfocused.

“Just hearing the earthquake alarm was horrible,” Hernandez said of a siren that rang during a 6.1 quake Saturday that was an aftershock of an even earlier and bigger temblor on Sept. 7.

“Something moves and …” he said, his voice trailing away at the unspeakable thought the whole pile could suddenly collapse. “There is a lot of nervousness, a lot of desperation. … This is the worst thing I have ever seen in my life, the worst.”

A total of 38 buildings in the Mexican capital — mostly apartment blocks or office buildings — collapsed in the Sept. 19 earthquake, and the first days saw a dramatic scramble with picks, shovels and bare hands to reach survivors.

Mexican marines, the lead force in many of the rescue efforts, said they had recovered 102 bodies and rescued 115 people alive from buildings toppled by the quake, which has killed 319 people including 181 in the capital alone, according to the latest death toll announced Sunday.

Thousands more have been left homeless because their houses or apartment buildings, while still standing, have been inspected and deemed uninhabitable.

Mexico City Mayor Miguel Angel Mancera reported that 7,649 properties have been examined and 87 percent of those are safe and require only minor repairs. But that means about 1,000 left standing have been determined to be uninhabitable — and the number seemed likely to rise as more are inspected.

Mancera also said Saturday night on Twitter that nearly 17,000 people have been “attended to” at 48 shelters, though it’s not clear how many of those are being housed there. Many are bunking with family or friends.

One by one the searches have closed down in recent days, after sniffer dogs were sent in and didn’t find life and thermal imaging devices turned up no body heat signatures. Then heavy machinery moved in to begin removing the mountains of debris. Empty lots began to appear where just days ago a building stood.

Now hopes were focused solely on concrete slabs at two sites: the former office block in the Roma Norte neighborhood, where around 40 people were believed to be missing, and an apartment building on the south side where searchers were looking for five people.

Both were ringed by rescuers, and atop the rubble, expert search teams from Mexico, Japan, the United States and Israel tunneled, measured and directed the removal of chunks of concrete.

At the Roma Norte site, after Saturday’s aftershock passed, work began again, grim, controlled, purposeful. An enormous crane lifted huge chunks of concrete slab. Rescuers have carved reinforced vertical tunnels into the heart of the wreckage, and from there they crawl into the narrow, claustrophobic horizontal spaces left between the collapsed floors.

But the last time someone was found alive was Wednesday, when a woman was pulled from the rubble. A couple of bodies were found Friday.

Volunteer rescue worker Johny Yebra said the smell of death is now heavy directly atop the rubble heap.

“All of us are doing the most we can,” Yebra said.

Beyond a ring of floodlights lies a makeshift collection of tents and tarps where anxious family members have endured rain, cold, grief and sleeplessness.

“It has been many days. Four, five … we can only wait and bear what happens,” said Enrique de Luna, the uncle of another missing man, Said Guzman.

As the names of the confirmed dead trickle in, one by one, their relatives are packing up their tents and going away.

That happened Saturday with the family next to Moreno’s. They didn’t say a word as they left weeping, and nobody had the courage to ask them what news they had received.

Everyone was even more on edge Sunday as rescuers told families they were going to lift a large slab that could reveal some information about anyone inside.

“We are very nervous. They’re going to remove the last rock in there,” said Dario Hernandez, Adrian Moreno’s friend.

Some fell silent and didn’t want to talk anymore.

Next to the tent someone had strung up a canvas sign: “Adrian, you are a warrior. Your family, your friends and Dario are waiting for you.”