Accounts with third-party service providers were used “for exfiltration or infrastructure,” according to a post by law enforcement on LockBit’s seized darkweb domain.
They’ve suggested people use VPN to connect to their email service for additional privacy.
https://protonvpn.com/support/no-logs-vpn/
"Proton VPN’s Swiss jurisdiction also confers additional benefits which are favorable for VPN services. In most countries, VPNs can be forced to log as the result of government orders, even if they are by default no-logs. However, within the current Swiss legal framework, Proton VPN also does not have forced logging obligations.
This notably differs from Swiss regulations for other online services such as email which is generally not no-logs and can require IP disclosure in the event of a Swiss criminal investigation. That’s why if your threat model requires hiding your IP from Swiss authorities when using Proton Mail, we recommend using a VPN or Tor."
They were probably referring to this event about a climate activist, which also mentions their suggestion of using Tor if you need to hide your IP address.
“ProtonMail also operates a VPN service called ProtonVPN and points out that Swiss law prohibits the country’s courts from compelling a VPN service to log IP addresses. In theory, if Youth for Climate had used ProtonVPN to access ProtonMail, the Swiss court could not have forced the service to expose its “real” IP address. However, the company seems to be leaning more heavily toward recommending Tor for this particular purpose.”
They’ve suggested people use VPN to connect to their email service for additional privacy.
https://protonvpn.com/support/no-logs-vpn/ "Proton VPN’s Swiss jurisdiction also confers additional benefits which are favorable for VPN services. In most countries, VPNs can be forced to log as the result of government orders, even if they are by default no-logs. However, within the current Swiss legal framework, Proton VPN also does not have forced logging obligations.
This notably differs from Swiss regulations for other online services such as email which is generally not no-logs and can require IP disclosure in the event of a Swiss criminal investigation. That’s why if your threat model requires hiding your IP from Swiss authorities when using Proton Mail, we recommend using a VPN or Tor."
They were probably referring to this event about a climate activist, which also mentions their suggestion of using Tor if you need to hide your IP address.
https://arstechnica.com/information-technology/2021/09/privacy-focused-protonmail-provided-a-users-ip-address-to-authorities/
“ProtonMail also operates a VPN service called ProtonVPN and points out that Swiss law prohibits the country’s courts from compelling a VPN service to log IP addresses. In theory, if Youth for Climate had used ProtonVPN to access ProtonMail, the Swiss court could not have forced the service to expose its “real” IP address. However, the company seems to be leaning more heavily toward recommending Tor for this particular purpose.”
proton mail is known to cooperate with law enforcement.
don’t trust them.