The landslides hit the Agam district of the province around 5:30 a.m., Antara news agency reported.
Rescue workers have dug out 11 bodies and hundreds of police officers and serviceman are still searching for nine others, officials said.
The landslides also destroyed 12 houses and damaged more than 29 acres of rice fields.
Antara said the landslides were triggered by recent rain fall.
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