Sensitive Documents requested by official government office through regular email

Before anyone asks, yes, this is an official government office asking us to send scans of very highly sensitive documents (almost equivalent to a passport) through a regular email attachment to their email account (valid .gov ending account).

I asked for a secure place to upload these and they gave me a robot speech pretty much.

Now considering that their email service provider isn't anything special and they probably won't do any extra like "click on this link here to …

account asking attachment documents email email attachment gov government office official passport privacy scans send upload valid yes