“She kept saying the weather was good,” he says. “She said it was rather warm, it was raining sometimes.”

The next morning, 26 August, Subhrasree left her hotel shortly after 7am.

Bhattacharya spoke to her on the phone, and the two continued messaging afterwards. Around an hour later, she told 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 3pm, he saw reports of the floods in the media. He started calling pilgrims in her group. 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.”