At least 52 people are reported to have died and an additional 20 are missing following rain-triggered floods in central China's Henan Province, a spokesman with the Henan flood control headquarters said Monday.

Torrential rains hit the mountainous regions in the western and southern parts of the province from July 23 to 25, resulting in heavy casualties in three cities - Luoyang, Nanyang and Sanmenxia.

Among the casualties, 37 of the dead were from Luoyang City, an ancient capital and home to the World Heritage site Longmen Grottoes.

The Longmen Grottoes site which receives more than 5,000 visitors each day had to be closed temporarily beginning on Saturday due to the flooding.

The Yihe River, which runs through the tourist spot, reached a flow rate of 1,380 cubic meters per second at the Longmen hydrologic station Sunday morning. Regulations call for the tourist destination to be closed once the flow rate surpasses 500 cubic meters per second, said Li Zhongye, director of Yihe river flood control office.

However, the flow rate returned to 634 cubic meters per second Monday afternoon, and the rate is likely to drop below 500 cubic meters per second by Monday night, Li predicted.

The staff is scheduled to begin cleaning up the scenic region and the tourist destination is expected to open on Tuesday or Wednesday, Li said.

The Longmen Grottoes had also temporarily closed in 2003 and 2005 due to rain-triggered flood.

Also, the magnitude of the loss is still being assessed, according to officials.