With 49 people on board a barge that sank in the Arabian Sea four days ago still missing, Indian Navy ships worked through the night, using searchlights to trace any movement in the pitch dark waters, as hopes of finding more survivors began to recede on Thursday.

The Navy on Thursday morning launched a fresh aerial search and rescue mission, deploying helicopters to scour the waters off Mumbai coast, where the accommodation barge P305 went adrift in Cyclone Tauktae fury before it sank Monday.