The first incident was reported from Motijhorna area where three persons including two children, aged two and five, and a woman, 29, were buried alive, officials said.
"These three were killed when their house was hit by the landslip and its walls came crashing down around 2 AM," Chittagong's additional commissioner Tahmilur Rahman was quoted as saying by bdnews24.Com.
The second incident occurred in Amin Colony where three children aged between two to 12 of the same family were killed after house wall collapsed on them following a landslide.
Amin colony is an illegal settlement where in June 2007, at least 127 people had died due to landslides in the hills of Chittagong after heavy rains.
The incident had prompted a periodic eviction of these illegal settlements on and below the hills of Chittagong, specially during the rains.
The evictions were underway when the landslip hit the settlements, the report said.