Flash floods and landslides killed at least 30 people on the Indonesian island of Sulawesi and left hundreds displaced, authorities said on Thursday.

Fifteen people remain missing, Indonesia search rescue agency spokesman Yusuf Latif said in a statement.

"The number of missing people might increase as many villages haven't reported the exact data of their missing residents," said the agency's chief in South Sulawesi, Muhammad Rizal.

The flash floods struck the North Luwu district of South Sulawesi Province after heavy rain on Monday caused three nearby rivers to burst. More than 4,000 residents were affected.

Hundreds of houses as well as government offices and public facilities were engulfed in mud from the floods. Dramatic TV footage showed dozens of houses partially submerged by thick mud up to their roofs.

Nearly 1,600 people were taking refuge in temporary shelters, the Search and Rescue Agency said on Wednesday. Villagers searched through their homes for pots and pans and other belongings to take to the temporary shelters.

Putri Nirmala Pakaya, whose three-year-old daughter was missing, pleaded with officials to help find her child who was swept out of her father's arms by the floods.

"We were sleeping when the floods suddenly hit our house hard three times. The third time, our house collapsed," she told AFP on Wednesday.

Indonesia frequently suffers from floods and landslides, particularly during the rainy season, though the situation is often made worse by the cutting down of forests.

Flooding killed at least 66 people in the Indonesian capital Jakarta in January and 80 people in Indonesia's eastern province of Papua in March.

(With input from agencies)