India airlifted drinking water into Male on Friday after a fire at a desalination plant led to severe shortages that have triggered scuffles and attacks on shops in the Maldivian capital.
Authorities declared a "disaster situation" after the fire on Thursday led to a drinking water crisis in Male, one of the world's most densely populated places.
India's air force flew bottled water onto the tiny island as authorities scrambled to repair the damage to the plant.
Much of the capital was still without drinking water on Friday afternoon and local media reported that angry residents fought and attacked shops that had rationed mineral water, while hotels in the capital said supplies were rapidly running out.
The crisis has not affected the atoll nation's upmarket tourist resorts, located on other islands, which by law have their own power generation and desalination plants.
But the private Minivan News website said damage to the water purification plant could take up to five days to repair.
"I think the situation is more serious than the government is admitting," a resident said, declining to be identified.
"We had water on tap for about an hour this morning, but that is hardly adequate."
Security forces were distributing water free of charge on the island, which measures just one square-mile (two square kilometres) and houses some 120,000 residents.
But activists said only those able to produce a Maldivian identity card were eligible for the free supplies, meaning thousands of migrant workers from Bangladesh, India, Nepal, Pakistan and Sri Lanka would be left out.
"Maldivians get water when they present ID cards. What about the thousands of unaccounted labourers in the Maldives?" asked political activist Shauna Aminath.
India said two more aircraft would arrive on the island later Friday with supplies.
It is also sending a navy patrol vessel with two water purification plants on board that can produce 20 tonnes of drinkable water a day between them.
Water is also being flown onto the island on all existing flights from neighbouring Sri Lanka, Minivan quoted the Maldivian foreign ministry as saying.
The ministry said a US naval vessel was also heading to the Maldives carrying water while China had also pledged unspecified support.
The Maldivian Red Crescent said it had deployed 24 staff and 60 emergency volunteers to help the government run water distribution points.
The low-lying island of Male has an efficient system of harvesting rain water, but the ground water cannot be used for drinking or washing, and residents rely heavily on treated sea water.
Many residents travelled to the nearby inhabited islands of Vilingili and Hulhumale, which were unaffected by the crisis, to stock up.