An accident at the construction site of a potassium fertilizer project in northwest China's Qinghai province has left seven workers dead and another four seriously injured on Thursday.

According to local sources, around 8:15 a.m., a truck belonging to Golmud Yingsheng Engineering Machinery Co. Ltd. was carrying 24 workers and construction materials and to the project site when it plunged into a huge salt pond, killing the seven workers on the spot.

The four injured, who were sent to a nearby hospital, were reported to be in stable condition by press time. The bodies of the dead were kept at the hospital.

Golmud Yingsheng Engineering Machinery Co. is held responsible for installing steel grooves for the ore-sunning workshop of Qinghai Salt Lake Potash Fertilizer Co. Ltd., located at the southern fringe of the vast Qaidam Basin.

The basin boasts a 5,000-sq-km salt lake, and numerous resources. Its proven reserve of potassium chloride amounts to 145 million tons, or 97 percent of the national total.

The project is designed to develop local economy by making good use of the abundant potash resources. It will have an annual production capacity of one million tons at a reduced cost of 2.6 billion yuan (US$313 million).