More than 300 people remained trapped in flood and 12,300 others were evacuated as of early Sunday in rain-soaked southwest China's Chongqing Municipality, said local authorities.

Information from the city's Tongnan County government said three townships -- Chongkan, Tai'an and Baizi -- and some other villages were flooded since 10 p.m. Saturday. Chongkan Township was out of contact due to destruction of facilities of communication and roads.

At least 600 residents were trapped, said Tongnan County government.

No casualties were reported thus far.

The flooding in Tongnan County occurred as heavy rains pounded the upper reaches of Qiongjiang River since Saturday morning, driving up the water level in the river's section in Tongnan County by 5.8 meters in four hours, said the county government source.

According to statistics given by Chongqing municipal flood control office, Chongkan township had a rainfall of 96 millimeters and Baizi township had 56 mm of rainfall from 8 a.m. Friday through to 10 p.m. Saturday.

The floodwater destroyed 128 houses and inflicted economic losses of 13.8 million yuan (2 million U.S. dollars) in Tongnan county alone.

The county government organized manpower, including firefighters and armed police to give a helping hand in the rescue operation. The rescuers helped 250 trapped people evacuate to safety as of 3 a.m. Sunday.

Rescue and relocation efforts were still going on.