A train ran into a group of railway workers on Thursday, killing 11 and injuring two, officials in China’s southwestern city of Kunming said, the deadliest rail accident in more than a decade.

The train, testing earthquake detection equipment, hit workers on a curved section of track at the city’s Luoyang Town railway station, the officials said.

The station in Yunnan province has resumed normal services, and the cause of the accident is being investigated, they added in a statement.

China’s rail network is the world’s largest, spanning more than 160,000 km (100,000 miles) and racking up billions of trips each year.

Though praised for its efficiency, it has drawn scrutiny after several high-profile incidents, such as a 2011 crash in the eastern province of Zhejiang that killed 40 and injured 200.

Nine were killed in 2021 when a train in the northwestern province of Gansu ran into workers on a section of the Lanzhou-Xinjiang railway.