China will put back into service 54 bullet trains that were recalled after a deadly train crash in eastern China fanned a furore about equipment flaws.
State news agency Xinhua says the recalled trains, which were meant to be used on the flagship Beijing-Shanghai high-speed rail line, have undergone "rigorous modifications and testing".
It did not elaborate further.
The trains were recalled by China's second-biggest train maker China CNR Corp Ltd in August, three weeks after 40 people were killed in a high-speed rail crash in the eastern province of Zhejiang.
The crash triggered public fury, bold media coverage and a freeze on approvals for new rail projects.
It also raised concerns about the safety of the country's high-profile and fast-growing rail network and threatened to undermine plans to export high-speed train technology.
Xinhua says some recalled trains have started running since November and all will resume service by 12 December.