Around 2:30 a.m. Sunday (6:30 p.m. ET Saturday) -- an hour after reporting five "visibly shaken" hostages had been released -- Kenya's National Disaster Operation Centre cryptically tweeted "major operations underway." What that meant was a mystery, and it didn't quell fears about what has happened or might happen to an unknown number of civilians who were still unaccounted for inside.
The same agency offered an update about three hours later stating that hostages were being held "in several locations," adding there was "no communications as yet." By then, government authorities had secured the mall's upper levels, though it was not known where the attackers -- and the threat -- remained.
Hours earlier, Kenya's president announced that 39 people, including some of his close relatives, were confirmed dead in the attack. Two gunmen, including one who was detained after being shot, are also dead.
Francis Kimenia, secretary to the Cabinet, tweeted another 293 people got treatment at three area hospitals, which "are appealing for more blood." The wounded range in age from 2 to 78, the disaster operations center said, urging people to "remember them in your prayers."
Al-Shabaab, an al Qaeda-linked militant group based in Somalia with ties to Nairobi's Eastleigh district and whose most recent attack of this scale came July 2010 in Uganda's capital, claimed responsibility for the carnage and vowed not to negotiate with Kenyan authorities. It claimed that "all Muslims" were escorted from the mall before the attack, suggesting its targets were people who didn't believe in their extreme form of Islam.
"The Mujahideen are still strong inside #Westgate Mall and still holding their ground," the group said late Saturday via Twitter. "All praise is due to Allah!"
Kenyan authorities, though, insist they have the upper hand, where it's now early Sunday morning. The last few hours of Saturday and the first few of Sunday, in Kenya, were largely quiet outside the mall except for movement
Police tweeted that the attackers "have been isolated and pinned down in a room by security forces." And Joseph Ole Lenku, the national government's cabinet secretary for interior and coordination, hinted that the worst should be over.
"Our security forces have taken control of the situation," Lenku said.
"Attackers of Westgate shopping mall have been isolated and pinned down in a room by security forces in the ongoing operation," the national police said on Twitter.
Kenya's president, Uhuru Kenyatta, blasted "the despicable perpetrators of this cowardly act (who) hoped to intimidate, divide and cause despondency among Kenyans and would like to (create) a closed, fearful and fractured society."
Kenya is no stranger to terrorism, including a 1998 bombing at the U.S. Embassy in Nairobi that left 213 dead and other attacks before and since tied to al Qaeda and related groups.
In a televised speech late Saturday, Kenyatta said his nation has "overcome" such attacks before, refusing to budge from its values or relinquish his security. And it will do so again, he promised.
"We shall hunt down the perpetrators wherever they run to," the president said. "We shall get them, and we shall punish them for this heinous crime.