A 7.0-magnitude earthquake struck a mountainous region in southwest China Tuesday night, leaving at least 13 dead and 175 others injured as rescue operations are in full swing Wednesday.

The quake zone, in Jiuzhaigou County of Sichuan Province, sits at a region that has been hit by at least three major tectonic earthquakes and other geological disasters over the past decade.

In May 2008, an 8.0-magnitude earthquake struck Wenchuan, about 200 km south of Jiuzhaigou, killing more than 80,000 people.

In April 2013, a 7.0-magnitude quake hit Lushan, about 360 km south of Jiuzhaigou, killing 196.

The quake-hit counties are located on the southeastern edge of the Qinghai-Tibet Plateau near the low-lying Sichuan Basin.

Jiang Haikun, an expert with China Earthquake Networks Center, said though the quakes were not related, they were all caused by crustal movement of Bayan Har block of the plateau, pushing the basin's borders.

The quake-prone area, known as Longmenshan fracture belt, is considered one of China's most active quake zones.

Jiuzhaigou also borders the county of Zhouqu in Gansu Province where a mudslide triggered by heavy rain left 1,765 people dead or missing on the same date seven years ago.

In June this year, a landslide hit Maoxian county, 180 km south of Jiuzhaigou, leaving 83 dead or missing.

Despite the disasters, Jiuzhaigou has a charm of its own. Part of the Tibetan and Qiang Autonomous Prefecture of Aba, Jiuzhaigou is particularly known for its indigenous ethnic communities, complex landscape, and unique scenery.

The Jiuzhaigou Nature Reserve covers 720 square km and has stunning plateau lakes, waterfalls, and mountains.

It was open to tourists in 1984. Tourist numbers have been climbing over the years. In 2016, a record 5.14 million tourists visited Jiuzhaigou.