Ticket sales on China's new Beijing-Shanghai high-speed rail are flagging after a deadly accident on the network, with some trains selling as few as 30 percent of their seats, state media said Tuesday.

More than 10 trains departed Shanghai on Monday with at least 200 empty second-class seats, each costing about 555 yuan ($86), data from the China Railway Customer Service Centre website showed.

Some trains on the new $33-billion line -- opened amid much fanfare on June 30 to mark the 90th birthday of China's Communist Party -- have seen as many as 700 tickets unsold at departure time, the Shanghai Evening News reported.

The fast link has been plagued by delays after lightning-triggered power shortages and corruption scandals -- and the July 23 collision near the eastern city of Wenzhou has fuelled fears about the safety of the high-speed network.

At least 40 people were killed and nearly 200 more were injured when a train rear-ended another after signalling equipment failed, marking China's worst ever high-speed train accident.

Even before the crash, there were concerns authorities had compromised safety in the drive to develop the high-speed system, already the biggest in the world.

China's state auditor has said construction companies and individuals last year siphoned off 187 million yuan from the Beijing-Shanghai project.

The revelation followed the sacking of former railway minister Liu Zhijun in February, who allegedly took more than 800 million yuan in kickbacks over several years on contracts linked to the network.