Six university students drowned on Wednesday after falling into a flotation cell during a study visit at a copper-molybdenum ore-dressing plant in North China's Inner Mongolia autonomous region, local emergency authorities said on Wednesday night.

The accident occurred at approximately 10:20 am on Wednesday at the plant, which is operated by a mining company under the China National Gold Group in Hulunbuir, according to the city's emergency management bureau. The students, all of whom attended Northeastern University in Shenyang, Liaoning province, were observing flotation processes when a grid plate collapsed, causing them to plunge into the flotation cell.

All six were rescued from the cell but later pronounced dead by medical personnel. A teacher was also injured in the incident.

Often seen in chemical or mining plants, a flotation cell is used to separate different materials from ore pulp by utilizing distinct physical or chemical features of different contents in the mixture.

The Inner Mongolia regional government will form a regional-level group to investigate the accident, China National Radio reported on Thursday.

ZhongJin Gold Corp, the holding company of the mine where the accident occurred, said in a statement on Thursday that it offers deep condolences to the victims and their relatives and apologizes for any negative social effects. Its stock price plunged as much as about 8 percent on Thursday, ending up with a loss of 4.4 percent.

Northeastern University told media outlet ThePaper.cn that the institution is still gathering relevant information and will issue a statement soon.

According to media reports, the students who died were from the School of Resources and Civil Engineering at Northeastern University, which offers majors such as mining engineering, mineral processing engineering, and safety engineering.

The school has an established cooperation with China National Gold Group's Inner Mongolia mining company, with their joint provincial-level engineering practice education center approved in 2020. The mine, located in Hulunbuir, is one of the largest copper processing facilities in China, with an annual production capacity of 76,000 metric tons of copper and 6,000 tons of molybdenum.

The incident has raised concerns about the safety management of student field visits to industrial sites and prompted universities nationwide to reinforce safety education for students participating in summer practice programs.

Many universities across China have issued urgent safety reminders regarding off-campus summer practice activities.

In a notice posted on Wednesday, Peking University's Youth League Committee urged student teams to fully understand potential safety risks and preventive measures before departure, conduct daily headcounts and health checks, and strictly adhere to safety regulations, including wearing protective equipment and knowing emergency contact information.

Hainan University's Youth League Committee also emphasized the importance of following designated routes, staying within permitted areas, and avoiding any contact with equipment or hazardous materials during site visits.

Hunan University of Finance and Economics highlighted the need to pay attention to floor conditions, overhead hazards, and moving machinery in factories, calling on students to question unclear safety protocols and to prioritize caution over embarrassment.

Meanwhile, Ordos Institute of Technology stressed that safety rules are often framed as a result of past incidents and thorough risk assessments, urging students to maintain curiosity while avoiding reckless behavior during internships.

The statement also underscored the responsibility of supervising teachers, describing them as "safety gatekeepers" who must treat the safety of students as a top priority.