CHENGDU - China is on high alert for secondary disasters like landslides in the quake-hit region in southwest China's Sichuan province as the rainy season approaches.

The provincial government has put in place an emergency response plan against geological hazards. Currently more than 400 professionals are identifying risks in the affected areas, especially around temporary settlements.

Based on the hazard evaluation, they will formulate plans for early warning, evacuation and emergency rescue to prevent the loss of lives and property caused by secondary hazards.

Qian Jiangpeng, chief engineer of Sichuan Institute of Geological Engineering Investigation, discovered many rocks had fallen to the edges of cliffs and cracks were found on the ground.

"Those rocks and soil will be dangerous for people and buildings under the mountain in case of heavy rain or a strong aftershock," Qian said on Friday.

The 7.0-magnitude earthquake hit Lushan county, Ya'an city on Saturday morning and has claimed nearly 200 lives. Ya'an is nicknamed the "city of rain" with an annual precipitation of 1,800 mm.

As of 4 pm Friday, 5,086 aftershocks had been recorded, including four between the magnitudes of 5.0 and 5.9, according to the provincial seismological bureau.

The top priority is to identify risks of landslides, mudslides and rolling rocks and prevent local residents from coming back to their dilapidated homes, said Sun Botao, director of the engineering mechanics institute under China Earthquake Administration.

Preventing geological disasters is crucial in the reconstruction work after the quake. Mass construction should be avoided in geologically active areas, said Sun.