Japan’s Financial Services Agency (FSA) has issued month-long suspension orders against two domestic cryptocurrency exchanges, CoinDesk reported.

Starting today, FSHO and Bit Station have been ordered to suspend their business for one month and strengthen their security measures. In addition, the regulator has also mandated Tech Bureau, GMO Coin, Mister Exchange, and Coincheck to enhance the security of their systems.

All six exchanges are required to submit a written improvement plan to the agency by March 22. The business improvement measures include proper management of user information, establishment of a system to appropriately implement confirmation and verification of transactions, and notification of suspicious transactions, among others.

The FSA has stepped up is oversight on domestic cryptocurrency exchanges after a major hack earlier this year in which Coincheck lost nearly $530 million worth of NEM tokens.

The regulator has also set up a cryptocurrency exchange industry study group in order to look into the institutional issues surrounding cryptocurrencies. The group comprises of representatives from academic institutions, cryptocurrency exchanges, and government agencies.