Kabul, Afghanistan (CNN) -- Eight suicide bombers attacked Kabul's Hotel Inter-Continental in a brazen, carefully orchestrated operation that began Tuesday night and continued into Wednesday, ending with their deaths and those of 10 others, officials said.
Two police officers are among the dead, according to the Interior Ministry.
"As a result of Afghan National Police, Afghan National Army and Coalition force's fast reaction and by air support of the NATO forces, eight suicide bombers were killed," the ministry said in a statement.
Mohammad Zahir, chief of criminal investigations for Kabul police, said Wednesday morning that casualty figures could rise.
"We are still searching the hotel; the death number may increase," Zahir said. Twelve people were injured, he added.
Interior Minister Bismullah Khan said "the situation is secure."
A spokesman for the Taliban, Zabiullah Mujahid, said in an e-mail that the suicide attackers entered the hotel after killing security guards at the entrance.
"One of the suicide attackers told us on the phone that they are in the lobby and chasing guests into their rooms by smashing the doors of the rooms," Mujahid told CNN in an e-mail he sent as the incident was unfolding.
The top of the hotel was ablaze, but flames were gone within a few hours. Smoke continued to rise from the building Wednesday morning.
By dawn, security forces were allowing reporters to approach the hotel, and some guests were seen departing.
Saiz Ahmed, a U.S. citizen in Kabul for a Ph.D. project, was among them. "I'm sure none of us thought we were going to make it," he said after having stayed on the floor of his darkened bedroom for more than five hours listening to gunfire and occasional bomb blasts. "I wrote my little will -- just in case."
The Taliban penetrated the hotel's typically heavy security in the attack, and one of them detonated an explosion on the second floor, said Erin Cunningham, a journalist for The Daily in Kabul.
Rocket-propelled grenades were launched from the roof of the hotel toward the first vice president's house. A few moments later, the hotel was rocked by three explosions, one of which knocked her off her feet, Cunningham said. U.S. forces were on the scene, she added.
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An hour later, ISAF said the Afghan security forces had cleared the roof and were clearing the rest of the hotel.
At 4 a.m., police believed that all the attackers were dead, "but one was alive and hidden and he started to resist" and continued to do so until 6:20 a.m., Zahir said.
At least one of the attackers detonated his explosives, said Afghan Lt. Gen. Mohammad Ayoub Salangi, the city's chief of police.
There were no indications that U.S. military or diplomatic personnel were at the hotel, U.S. officials told CNN.
A news conference had been scheduled to take place in Kabul on Wednesday to discuss the planned transition of security from international to Afghan forces that U.S. President Barack Obama announced last week. Obama was briefed on the attack while en route back to Washington from Iowa, White House spokesman Jay Carney told reporters.
Members of the Afghan National Security Forces were on the scene, but the city police had the lead, ISAF Maj. Jason Waggoner said in a statement. Waggoner said ISAF forces provided "some limited assistance."
The United States condemned the attack on the hotel, with State Department spokeswoman Victoria Nuland saying it "once again demonstrates the terrorists' complete disregard for human life."
The hotel was developed by the InterContinental Hotels Group and opened in 1969. But it has had no association with the group since the Soviet invasion in 1979, though it continues to use the name and logo without connection to the parent company.
The incident came on the same day that Lt. Gen. William B. Caldwell announced that NATO and other members of the international community involved in Afghanistan have decided to increase the number of security forces in the Afghan National Army and the Afghan National Police to 352,000.
The current number of Afghan National Army and Afghan National Police is about 300,000, the commander of the NATO training mission in Afghanistan and commanding general of the Combined Security Transition Command told the Atlanta Press Club.
The increased number will be sufficient to give the Afghans security without coalition forces having to do it, he said.
Tuesday's attack recalls a November 2008 assault on luxury hotels in Mumbai, India, which left more than 160 dead, including nine of the 10 gunmen who launched the attacks.
Officials said the gunmen targeted the Oberoi and the Taj Mahal hotels for their popularity with international travelers and tourists. The Taj Mahal was set afire.
The three-day stand-off between gunmen and police ended with the capture of Mohammad Ajmal Kasab, the only surviving gunman. Kasab was sentenced to death in 2010 and is awaiting an appeal of the decision to the Supreme Court in New Delhi. India says Kasab has told investigators that he and the others were trained for more than a year in Pakistan by Lashkar-e-Tayyiba, a banned Islamic militant group.CNN's Reza Sayah in Islamabad, Pakistan; Matiullah Mati in Kabul, Afghanistan; Tom Watkins in Atlanta; Barbara Starr, Larry Shaughnessy and Elise Labott in Washington; and journalist Jonathan Boone in Kabul contributed to this report.
