KABUL, Afghanistan — So much had changed in the three years since the Taliban blew up the barrier wall at Sariposa prison and sprang 1,000 inmates: imposing rows of concrete blast walls backed by razor wire, floodlights, video cameras, sandbags, and 40 well-armed American soldiers watching from perimeter guard towers with the Afghan police.
Kandahar's largest prison had become so secure, said an American military officer giving a tour this year, that the only way to break through was to "put a nuke on a motorcycle."
Or to dig 4,000 feet of underground tunnel and pop up into the middle of the prison, as the Taliban did Monday morning, freeing one-third of the inmates and collapsing months of effort to improve security at the jail.
The audacious plot freed nearly 500 fighters through the tunnel dug over more than five months and equipped with electricity and air pipes, which suggested that the insurgents remain formidable and wily opponents.
The plan was so closely held that one young Taliban fighter who got out said he knew nothing of it until a fellow inmate tugged his sleeve to wake him in the night and led him to the 3-foot-wide tunnel, which ran more than half a mile from a hole in a cell's floor and came up in a nearby house. From there, a waiting car took the fighter a few miles away, where he hailed a taxi to safety.
"I was just praying to God that he would free me," said the fighter, Allah Mohammed Agha, 22. He had been held for 28 days. "Last night was the night that my dream was made true."
Prison officials say they discovered the breach about 4 a.m. Monday, a half-hour after the Taliban says it had gotten all the prisoners safely to a house at the other end of the tunnel. The city's police mounted a massive search. They shot and killed two inmates who tried to evade capture and re-arrested 26, said Tooryalai Wesa, the provincial governor.
But there was no ignoring that the Taliban had pulled off a daring success under the noses of Afghan and NATO officials.
"This is a blow," presidential spokesman Waheed Omar said. "A prison break of this magnitude of course points to a vulnerability."
At least 486 inmates escaped, most of them Taliban fighters, according to Wesa. The Taliban said that it had freed more than 500 of insurgents and that about 100 of them were commanders — four of them former provincial chiefs.
The Taliban this month has penetrated some of Afghanistan's most aggressively defended facilities. Attackers have killed Kandahar's police chief inside his headquarters, assaulted a crowded Afghan army base in Laghman province, and shot up the hallways of the Ministry of Defense in Kabul. The security breaches have raised concerns about the Afghan government's ability to protect itself from insurgents as U.S. and NATO forces begin to withdraw.
Work on the tunnel had been ongoing for months, according to Taliban spokesman Zabiullah Mujahid. The tunnel ran 10 feet underground from a house about 4,000 feet from the southwestern corner of the prison complex, said Gen. Ghulam Dastagir Mayar, the prison warden.
The tunnelers reached the surface inside the "political wing" of the prison and ushered out the detainees before dawn. Mayar said that the security guards were not asleep but blamed the breach on an undermanned staff. "We cannot put security guards in every room," he said.
Members of Parliament were scathing about the lapses. Some questioned whether guards or police officers were bribed not to notice the tunnel's construction.
"It's a big achievement for the Taliban and shows a big failure and weakness in the government," said Muhammad Naiem Lalay Hamidzai, a Parliament member from Kandahar.
"The Taliban gains two things from this jailbreak," he said. "First ... it sends a message that they can do whatever they want, even at the heart of the most secure and important jail, and it allows them to strengthen their ranks with more manpower."
The U.S. military's Task Force 435, which oversees detainee issues, has two advisers at the site, along with about 40 U.S. soldiers from a military police battalion.
On a tour of construction at the prison in February, Lt. Col. John Voorhees, the battalion commander, said, "We're trying to make the government the best alternative, in the right way."
"This is the future," he said.
Information from the Washington Post, New York Times and Associated Press was used in this report.