India, Feb. 27 -- The sun had just slipped behind the horizon when 39-year-old Bobildul Haque and his wife returned home from the paddy fields of Rowmari Char in Assam's Barpeta district. Their feet were heavy with mud, their bodies exhausted after a long day's work. In the fragile world of the char - the shifting sandbars of the Brahmaputra - evening brings not only darkness, but uncertainty.

But as they stepped inside their modest home, they realized that something was wrong.

Their eldest daughter, 14-year-old Rehena Khatun (name changed), was missing.

They asked their three younger children. The siblings said Rehena had stepped out in the afternoon, telling them she would return soon. She never did.

Panic set in. Bobildul ran from ...