The Chinese D train derailed with two of its carriages falling off a bridge after being crashed into by another train, reports suggest. The number of casualties, however, is still unknown, according to the official Xinhua news agency.
The train, travelling from Hangzhou to Wenzhou, went off the rails in eastern China's Zhejiang province around 8:30pm (1230 GMT), it reported, citing local firefighting sources.
It is thought to have come to a halt on the bridge near Wenzhou when its power failed following a lightning strike. A second train collided from behind, pushing carriages of the D train off the bridge.
The D train represents China's first-generation bullet trains. Running on regular track, they are capable of travelling at 150kph and are not part of the new high-speed network.
China is spending billions on building a high-speed rail network, with Premier Wen Jiabao on June 30 formally opening a flagship $33 billion line from Beijing to Shanghai.
The huge investment has made the sector a hotbed for corruption. China's state auditor has said construction companies and individuals last year siphoned off 187 million yuan ($29 million) from the Beijing-Shanghai project.
