BEIJING — China's Ministry of Transport on May 22 launched a Level II emergency response, the second highest of the four-tier system of emergency responses, after a series of earthquakes rattled Southwest China's Yunnan province and northwestern Qinghai province.

Some sections of the highways near the quake-hit areas in Yunnan were damaged by falling rocks, causing traffic disruptions, while several bridges near the affected region in Qinghai collapsed, the ministry said.

The ministry is working with local transport authorities on damage checks and road repairs, it said.

Four earthquakes over 5.0-magnitude struck Yangbi Yi autonomous county in Dali Bai autonomous prefecture of Yunnan from 9 pm to 11 pm on May 21 Beijing Time. The tremors were felt in all 12 counties and cities of the prefecture, with Yangbi being the worst hit.

Hours later at 2:04 am on May  22, a 7.4-magnitude earthquake jolted Maduo county of Golog Tibetan autonomous prefecture, according to the China Earthquake Networks Center. The county is located over 4,000 meters above sea level.

The country's national observatory said that the affected areas in Yunnan will mostly see sunny and cloudy weather on May 22 and 23, and warned that potential showers starting on May 24 may reduce visibility. It also suggested authorities in Qinghai to guard against the adverse effects of sleet and low temperature on rescue and resettlement work.