An investigation into a high-speed rail crash in China that killed at least 40 people and injured nearly 200 has ended, but the findings will not immediately be made public, the government said Tuesday.

The July 23 crash in the eastern city of Wenzhou triggered a flood of criticism of the government and led authorities to freeze the rapid expansion of China's ambitious high-speed rail network, already the world's most extensive.

The investigation into the disaster -- China's worst rail accident since 2008 -- has ended and a report on the findings is being compiled, Huang Yi, spokesman of the State Administration of Work Safety, said in a statement.

"The investigation team ... will quickly hand over the report, as well as publicise the findings of the investigation," Huang said, without putting forward a date.

Earlier state press said the accident was caused by "poor management," but government departments have refused to comment publicly on the investigation.

"The main problem lies in the poor management of local railway administration," the Beijing News quoted Wang Mengshu, deputy head of an investigatory panel into the accident, as saying late last month.

"They had all the best equipment, but did not maintain it well. The failure of their facilities, along with inadequate operation, resulted in the tragedy."

China has built the world's largest high-speed rail system from scratch in less than a decade, but the rail ministry has been accused of overlooking safety in its rush to develop the country's vast transport network.

Earlier this year the former railway minister, who had overseen construction of much of the high-speed network, was sacked and placed under investigation for corruption.

In the weeks following the accident, authorities announced a halt to new train projects, introduced new speed restrictions on bullet train lines and recalled 54 of the high-tech trains.