Death toll increases

Rescuers are picking through rubble in a desperate search for any survivors.

Homes, churches and schools were among buildings flattened in the quake. Some hospitals were left overwhelmed and in need of supplies.

An unknown number of people are missing and about 5,700 have been injured, officials say.

The disaster compounds problems facing the impoverished nation, which is already reeling from a political crisis following the assassination of its president last month.

At least 11 of those who died in the flooding Friday were students, according to Sutopo Purwo Nugroho of the disaster mitigation agency. Some students are still missing. The flooding was in Mandailing Natal, North Sumatra.

Some of the students were buried under debris and mud after the Aek Saladi river overflowed, according to state media.

Torrential rains over the last four days have sparked widespread flooding and triggered landslides in southwestern parts of the Indian Ocean island. At least 177 people have died and almost half a million others have had their lives disrupted.

As search and rescue teams look for more than 100 people who remain missing, and Sri Lanka's military in boats and helicopters struggle to reach marooned villagers with food and clean water, charities are warning of a looming health threat.