Eight people died and 18 are feared trapped inside a cargo vessel which sank on a river in Indonesia's Borneo island, an official said Saturday, though state media says the tolls could be much higher. The Sari Mulia went down after encountering strong currents 100 kilometres (60 miles) from the city of Banjarmasin, in South Kalimantan province, late Friday. "Eight people were killed. It's estimated that 18 people are still trapped in the vessel," Health Ministry crisis centre head Rustam Pakaya told a foreign news agency, adding 117 people had so far been rescued. But the Antara state news agency said the number of dead and missing could be far higher because many of those who boarded the boat could have done so without a ticket and would not appear on the manifest.