It was just past 10 p.m. when the hulking bus sputtered to a stop at this military checkpoint, 70 miles from the front lines of this country's civil war.
The passengers quietly exited the bus and stood behind the razor wire, identification cards in hand. The men split off into one line. A far smaller number of women went into a separate row, some cradling sleeping babies.
But it was the women's line that took twice as long to navigate. That's because female officers rummaged through women's purses and bags before moving on to their breasts, even feeling the insides of their bras for explosives.
They didn't stop there. They patted down their groins and occasionally looked inside their underwear. Pregnant women routinely had their swollen bellies squeezed or prodded, just to make sure.
Women are often singled out for scrutiny because, in Sri Lanka's 25-year civil war, more than two-thirds of the Tamil Tiger suicide bombers have been women, according to experts from the New York-based Council on Foreign Relations.
The group, known officially as the Liberation Tigers of Tamil Eelam, has had the highest number of female suicide bombers in the world and was the first to widely use women in suicide attacks, according to the FBI and military experts.
A woman from the rebel group's Black Tiger cadre killed former Indian prime minister Rajiv Gandhi in 1991. More recently, on Feb. 9, a female suicide bomber from the Tamil Tigers detonated explosives at a checkpoint as female officers in the Sri Lankan army frisked her. The blast killed 28 people, according to government reports.
In Sri Lanka, an Indian Ocean island of 21 million where modesty is a virtue and women still wade into the sea in billowing saris, the focus on women at checkpoints can be painful - some turn red and even cry as they are being frisked.
Overall, Sri Lanka's stepped-up security - the routine traffic stops, countless checkpoints, car searches, bag checks and frisking - is testing the boundaries of what people here are willing to endure for the sake of their safety.
The experience could serve as a barometer for other countries forced to balance civil freedoms and privacy rights against the need to protect residents from terrorism.
Across much of South Asia, suicide attacks and bomb blasts are increasing.
In India, which suffered terrorist attacks in eight cities last year, frisking has become a part of daily life at malls, movies theaters, five-star hotels and even hospital emergency rooms.
Women's groups are pushing not only for more female guards, but also for some basic protections, such as separate curtained-off areas, more metal-detecting wands and fewer hands-on searches, which some rights groups say are an affront to women in a region where nakedness is still highly taboo.
"You really feel humiliated. Even when a female is putting her hands all over your body, men are often watching," said Roshan Farid, 39, a researcher for a women's rights group in Sri Lanka.
She passes through about 14 checkpoints during her trips from the capital of Colombo to the northern region of Mannar.
"On my way home, there are about nine checkpoints where no female officers are working."
In Sri Lanka, the level of security is ratcheted up after every attack.
The country is hyper-militarized, and the movement of its residents is tightly regulated, especially now that the Sri Lankan army has cornered the LTTE in a tiny patch of jungle.
"The frisking in Sri Lanka now is very intimate, and it feels shocking and rude," said Ila Kumar, an Indian woman who frequently makes business trips to Colombo. "But it's a question we are asking in India and maybe all over the world, also: Is it worth it if it stops even one female with a bomb in her bra?"
Sweeping emergency regulations introduced in August 2006 in Sri Lanka have given the security forces expansive powers of search, arrest, detention and seizure of property.
They are also permitted to hold individuals in unacknowledged detention for up to 12 months, according to Human Rights Watch.
Sri Lanka's defense minister, Gotabhaya Rajapaksa, the brother of President Mahinda Rajapaksa, defended the searches, comparing the country to the United States after the Sept. 11, 2001, attacks, when some Americans bristled at having to remove their shoes and belts at airports.
"People complain about checkpoints and roadblocks," the defense minister, who once lived in California, said in an interview.
"But what we are doing is saving innocent lives. This is what terrorism has done to us. We don't want to do it."
Few people question the need for checkpoints in a conflict that has claimed 70,000 lives and is being waged by a group that the United States has labeled a terrorist organization.
Tamil Tigers say they want a separate homeland after decades of discrimination at the hands of Sri Lanka's Sinhalese Buddhist majority.
With the conventional ground war in Sri Lanka apparently nearing an end, experts expect suicide attacks to increase, especially in urban areas. That could put the country's minority Tamil civilian population at risk of increased ethnic profiling, referred to here as Traveling While Tamil.
Some groups have suggested allowing a third party to monitor checkpoints, and several women's groups have demanded that female guards be present, especially at rural outposts, which often have only male guards.
"No one is disputing the need for checkpoints," said Meenakshi Ganguly, a researcher at Human Rights Watch.
"But there needs to be more training in Sri Lanka to screen civilians in a respectful way. Right now, it's the behavior of a victor's army. Tamils feel like second-class citizens."
The heart of the war has centered on the discrimination that Tamils, who are largely Hindu and make up about 12 percent of the population, have felt for decades in Sri Lanka, said Beate Arnestad, a Norwegian filmmaker who made a 2007 documentary, "My Daughter the Terrorist," about two female Tamil Tiger suicide bombers.
"Who won't be brainwashed if the only experience you have in life is such a cruel war," Arnestad said.
"The female suicide bombers think, 'I would rather die with a weapon in my hand, defending the cause, than become a victim of the war.' They think the Tigers saved them, the Tigers are the way to have freedom," Arnestad added.
Many of the women joined the Black Tiger squad because they felt respected and secure within that force, after reports of Sri Lankan army soldiers sexually assaulting Tamil women, Arnestad said.
For many women, the fear of checkpoints has been heightened by stories of rape and harassment at the hands of those supposedly trying to restore order.
Padmini Ganesan, 65, a Tamil schoolteacher, said many Tamil women remember the 1996 case of Krishanthi Kumaraswamy, an 18-year-old student who had just completed her school exams when she tried to cross a checkpoint in the northern city of Jaffna.
She was gang-raped and strangled by Sri Lankan soldiers and a police officer, according to published reports at the time. To cover up their crime, the perpetrators also killed the student's mother, her brother and a neighbor who helped look for her.
The Sri Lankan government, which was at first slow to investigate the case but eventually yielded to international pressure, convicted the soldiers and the police officer, sentencing them to death.
"Every Tamil remembers the Krishanthi case," Ganesan said. "For us, the checkpoints are sort of a slow-motion thing, the trauma and the fear that we go through."
