WUHAN - A total of 20 trains have been suspended after a roadbed of a section on the Beijing-Guangzhou line in Central China's Hubei province collapsed Thursday morning, railway authorities said.

The Wuhan Railway Bureau said the collapse occurred at around 1 a.m. Thursday, causing 20 ordinary trains on the line to temporarily halt their services. The high-speed trains haven't been affected.

An emergency response plan has been launched, and a team of 500 engineers and workers, as well as machinery, have been mobilized to cope with the collapse, according to the bureau.

The cause of the incident is under investigation.