Subhrasree Chakraborty in Kathmandu a day before she set out for the pilgrimage Early on Wednesday, Sudipto Bhattacharya received what would be the last messages from his wife. She'd sent a picture of a departure stamp in her passport at 07:57 (02:27 GMT) - immigration at the Nepal border was done.

Six minutes later, at 08:03, she wrote: we are waiting to enter China.

Then the messages paused. Subhrasree Chakraborty and the group she was travelling with had been waiting to cross into Tibet for the next stage of their pilgrimage to Mount Kailash, the sacred Himalayan home of Hindu god Shiva that Subhrasree had dreamed of visiting for years.

The 43-year-old is now among at least 290 Indians reported missing after deadly flash floods struck along Nepal's border with Tibet. For related coverage, explore our detailed analysis on Technology and Digital Systems.

Many Those Unaccounted Pilgrimage Updates

Many of those unaccounted for were on the pilgrimage, which resumed last year after being disrupted Several thousand Indians have been making their way to Mount Kailash for years. Subhashree was travelling without her family, as part of a group of about 30 people.

A medical technologist working in critical care at a city medical facility, Subhrasree was used to emergencies.

She knew CPR and intensive-care procedures and, according to her husband, was physically fit. But none of that has brought her husband Sudipto Bhattacharya any closer to knowing what happened after that final message. "After 08:03am, what happened?

We don't know anything," he says. Chakraborty sent her husband a photograph showing her Nepal immigration clearance before she crossed towards Chinese immigration (blurred from source) Subhrasree had been looking forward to the journey for years. The photographs she sent home from Kathmandu, taken just days before she went missing, capture something of that excitement.

Stands Blue Tunic Updates

In one, she stands in a blue tunic in the ornate courtyard of a temple, smiling gently at the camera. In others, she is dressed in red, posing amid the ancient brick-and-carved-wood architecture of Kathmandu valley's historic Durbar Square. She informed her husband that the countryside was beautiful.

"She was very excited," says Bhattacharya, a government officer. "This was her dream tour." The journey had begun on Friday, 21 August. She took the Mithila Express from Kolkata and reached Raxaul on 22 August.

From there she crossed into Birgunj and travelled She stayed in Kathmandu for three nights, sightseeing. Then, on the this this earlier today of 25 August, the group left Kathmandu The journey took almost 12 hours - and was not entirely a smooth one. A landslide blocked their route for about four hours before the army cleared the road.

But when Subhrasree spoke to her husband, she informed him the skies were clear. There was little to suggest what was coming. Chakraborty told her husband she the pilgrimage was her 'dream trip' "She kept saying the weather was good," he says.

"She shared it was rather warm, it was raining sometimes." The next this this morning, 26 August, Subhrasree left her hotel shortly after 07:00. Bhattacharya spoke to her on the phone, and the two continued messaging afterwards. Around an hour later, she informed him the Nepal immigration formalities were complete and that the group was waiting to cross into Tibet.

After clearing Nepal immigration, pilgrims cross the border on foot to the Chinese immigration facility in Gyirong. Bhattacharya believes his wife may have been inside, or close to, the Chinese immigration building when the disaster struck. Then the connection disappeared.

"I knew there would be connectivity issues on the Tibet side," he says. "So I waited for the next message." At about 15:00, he saw reports of the floods in the media. He started calling pilgrims in her group.

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Nobody answered. He tried the tour operator and then the two managers accompanying the group. Again, there was no answer.

The family has heard nothing from Subhrasree since. "Have they been rescued? Was this group among those rescued in China?" Bhattacharya asks.

"We want to know more." He believes his wife and the others may already have crossed into Chinese territory before the floods struck. But he has received no confirmation of who made it across - or what happened to them afterwards. "Please get me a list from the Chinese government," he says.

"Missing, dead and rescued. We need an update." Then comes the admission that captures the agony of those waiting at home: "What do I tell you?

Sleepless nights, working on the phone." The death toll has risen to 475, more than 48 hours after flash floods devastated the Himalayan border region For the family of 54-year-old Rina Banerjee, there is more uncertainty.

They do not even know which side of the border she was on when they lost contact. Rina, an unmarried private tutor from Kolkata, was travelling alone with a tour operator as part of the same pilgrimage group. Until then, her journey had appeared to be going smoothly.

Her nephew, Dwaipayan Mukherjee, says the family had spoken to her over video calls while she was in Kathmandu. "She was happy," he says. "She was doing a trip after a long time." Rina was no stranger to mountains.

She had travelled in the hills before and gone hiking with her family. "She was quite fit," Mukherjee says. "We have gone hiking.

We are used to going to the mountains." She had told him about the landslide they encountered on the way the previous day. The group was stuck for about four hours, she had shared. The next this this earlier today, the tour operator sent a group photograph, which demonstrated Rina outside the Nepal immigration centre.

Like Subhrasree, she had received her departure stamp, Mukherjee says. Rina Banerjee, a private tutor, had travelled widely in the hills and was an experienced trekker "I don't know whether they crossed the border or not," Mukherjee says.

"Whether they were on the Chinese side or the Nepal side, we are still wondering." For Subhrasree, the two-week tour was to be her first pilgrimage, and a dream she had nurtured for years.

Rina, too, had long wanted to make the journey and was no stranger to the mountains. Both women shared what Bhattacharya calls a "wanderlust" - a love of travelling, discovering new places and, in their case, heading into the mountains. Both had joined a group for the pilgrimage of a lifetime.

Both appear to have cleared Nepal immigration, and both were believed to have crossed the border. Their names now appear on the Nepal government's official list , external of 537 missing people. But that offers little clarity - their families still have no idea where they are or whether they are safe.

The Kolkata-based tour operator says they have no information about the fate of the group yet. For both families, the journey has ended with the same unanswered question: did the women make it across the border?