At least three vessels have grounded in the devastating tycoon that hit Indonesia on Friday.

Local media reported that the 500-dwt passenger/cargoship Sabuk Nusantara 39 (built 2014), operated by the Indonesian government, was forced ashore after it broke lose from its moorings at a dock in Sulawesi.

Meratus Line's 7,400-dwt MPP Merantus Kendari 1 (built 1993) grounded but was later refloated and moved away from the coast.

Another unnamed vessel also grounded, but was refloated and anchored.

The extent of damage to the ships is not clear.

The Guardian reported on Monday that victims will be buried in mass graves.

The death toll stood at 832, but authorities fear that thousands may have died in the six-metre tsunami following an earthquake.