BEIJING, July 23 (Xinhua) -- As rainfall continued to batter northern China, relevant departments have been required to make necessary preparations for possible disasters caused by the rain.

China's Ministry of Emergency Management (MEM) on Sunday called for better efforts to mitigate disasters and reduce casualties during the flood season.

MEM's Vice Minister Huang Ming said that late July and early August is a "critical stage" for fighting floods and providing relief.

The Yellow River Flood Control and Drought Relief Headquarters, the second longest river in China, issued a new alert for floods in its upper reaches Monday morning.

The water level in the section of Lanzhou, the capital city of northwest China's Gansu Province, along the Yellow River, has risen rapidly due to heavy rain.

A hydrologic station located in Lanzhou recorded a water flow of 2,700 cubic meters per second at 5:00 a.m. Monday morning, and the figure rose to 3,600 cubic meters per second at 8:00 a.m.

The headquarters has asked relevant departments in the upper reaches of the Yellow River to strengthen precautions against floods and landslides, as well as evacuate people from affected areas, and enhance monitoring along the river and dikes.

Safety personnel have been required to promptly update and report information regarding floods, while reservoir management agencies have also been demanded to release flood waters according to instructions.

The water resources department of northeast China's Heilongjiang Province said Monday that water levels of the main stream of the Heilongjiang River are currently higher compared to the same period in history, due to lingering rainfall. Water levels of several main streams have already exceeded the warning level.

The provincial meteorological observatory forecast rainstorms and high winds in the following days in the province.

In northwest China's Ningxia Hui Autonomous Region, more than 5,200 residents have been evacuated as torrential rain has battered Helan Mountain since Sunday.

The region saw heavy rain between Sunday night and Monday morning. The maximum rainfall during this period reached 277.6 millimeters in Helan Mountain, and floods have formed in the eastern areas at the foot of the mountain.

The regional flood control and drought relief headquarters have organized relevant departments including public security, fire, water resources and traffic to evacuate residents from affected areas.

An auxiliary police officer remains missing after being washed away by floods during the evacuation. A search operation is underway. An injured police officer is also receiving treatment at the hospital.

In north China's Inner Mongolia Autonomous Region, floods triggered by torrential rain have left 12 people dead and three others missing, local authorities said Monday.

The regional meteorological observatory has issued a red alert for rainstorms, warning that rainfall will continue in the following days and may cause floods and landslides in cities and towns.

Inner Mongolia has been hit by heavy rain since the flood season started this month. A number of roads and hydrological facilities have been damaged.

More than 338,000 residents and over 157,000 hectares of crops have been affected by heavy rain. More than 300 houses have been destroyed, and a total of 9,307 people have been relocated, according to the local authorities.

The direct economic losses in the region were estimated at 637 million yuan (94 million U.S. dollars).

Meanwhile, Beijing, Tianjin and Hebei Province are expecting heavy rain on Monday and Tuesday, under the influence of Ampil, the 10th typhoon this year, the Beijing Meteorological Service said Monday.

Beijing has issued a blue alert warning against mud flows and landslides in mountainous areas.