Work teams have abandoned rescue efforts at a military hospital near Chechnya which was destroyed by a truck bomb which killed 50 people.
"There are no longer any human remains in the area covered by rescue teams," Emergency Ministry officer Sergei Salov told Interfax news agency on Sunday, as Russian TV reported the return to Moscow of a planeload of rescue workers.
The Emergency Ministry put at 50 the death toll from Friday's blast in the town of Mozdok, site of a big Russian military base, after brigades with sniffer dogs had sifted through piles of debris overnight.
More than 70 people remained in hospital, with the most serious cases airlifted to Moscow and St Petersburg.
Authorities blame Chechen rebels but also accused local commanders of failing to protect a high-profile target, where many servicemen hurt in the conflict were sent for treatment.
The base is a major staging point for Russia's campaign to quash Chechen separatism in the mainly Muslim region. Its commander has been suspended and the hospital director detained in connection with an inquiry.
President Vladimir Putin vowed that the blast, one of several attacks in recent months that has killed many people, would not derail his plan to end 10 years of Chechen insurgency. That plan, rejected out of hand by separatists, has as its centrepiece an election for Chechen president in October.
NTV television showed heavy equipment being moved into the blast site to begin tearing down the remnants of a wall still standing. It said experts had determined that the structure was so weak that it was not necessary to use explosives.
The television also said some distraught relatives still had no word of loved ones, including servicemen undergoing treatment, who did not appear on lists of dead and injured.
Mozdok lies in North Ossetia, one of a patchwork of regions in the Caucasus, where a day of mourning was declared for Monday.
Witnesses said an explosives-packed truck driven by a single man smashed through the hospital gates on Friday evening before exploding and bringing down most of the building.
Since seizing a Moscow theatre for three days last October, rebels have been emboldened in staging attacks on tens of thousands of Russian troops inside Chechnya and on other targets elsewhere in the country. But all but the most extreme separatists have denounced the use of suicide attackers.
In Chechnya, where campaigning for president is gaining pace, the region's acting president formally announced his candidacy at a ceremony attended by hundreds of Muslim clergy. A half dozen hopefuls have said they will run.
Akhmad Kadyrov, a former clergyman, was installed by the Kremlin as local leader in 2000 after Russian troops took nominal control of much of Chechnya in their second post-Soviet drive to crush separatism. His office announced his candidacy last week, independent of all political parties.
"I cannot, for the sake of my own well-being and peace of mind, remain to one side and observe as Chechnya slides into chaos," Interfax quoting him as saying in eastern Chechnya.
The poll is intended to give Chechnya its first elected leader since Aslan Maskhadov, voted into office in 1997 during a period of de facto independence, but chased from power when Russian forces poured back into the region.