Where is the bitFlyer server?

Excuse me, I'm curious about something regarding the bitFlyer exchange. Could you please clarify for me where exactly their servers are located? I understand that the location of servers can have implications on security, latency, and regulatory compliance, so I'm keen to learn more about this aspect of their operation. Is there any information publicly available about the specific locations of bitFlyer's servers, or is it something that they keep confidential for security reasons?