BTCChina, one of the leading Bitcoin exchanges in China, is permanently shutting down, the company announced on Twitter.

The news come after a few weeks of rumors that China will ban all cryptocurrency exchanges in the country. The rumors were never officially confirmed, and major exchanges in the country—including BTCChina—initially said they hadn't received any official directives from the authorities.

It's not clear what has changed in the meantime, but BTCChina has now announced it will stop all trading on September 30. The company said some of its products, such as the BTCC mining pool, will remain operational.

1/ After carefully considering the announcement published by Chinese regulators on 09/04, BTCChina Exchange will stop all trading on 09/30. — BTCC (@YourBTCC) September 14, 2017

2/ BTCC products, including BTCC Pool, are not affected by this change. Please contact us at support@btcc.com if you have any questions. https://t.co/r3HvINU20p — BTCC (@YourBTCC) September 14, 2017

BTCChina is the fifth largest Bitcoin exchange in the world by trading volume according to CoinMarketCap, and the third largest in China.

While this news still doesn't mean that China plans to officially ban all cryptocurrency exchanges in the country—some have speculated that the Chinese authorities would merely tighten the regulation of crypto exchanges—it's a very good indication that something of the sort may happen.

It's been a rough couple of weeks for Bitcoin and other cryptocurrencies. The global market share of cryptocurrencies shrunk considerably after last month's news that China would ban all ICOs (initial coin offerings) in the country. Most cryptocurrencies have declined significantly in value since.

Disclosure: The author of this text owns, or has recently owned, a number of cryptocurrencies, including BTC and ETH.