One of my co-workers received a similar email from one of her email contact's address -- apparently it's one of the hot, new fraud schemes. Never, ever, send money based on an out-of-the-blue email contact. Even if someone is stuck somewhere outside of CONUS, they can find a way to call you on the phone so that you know it's really them.

Not that people normally think about it, but for close enough friends and family who you might render that kind of assistance to, it might be worth agreeing to a passphrase in advance that they'd include in a message to authenticate that it's from them. It sounds stupidly cloak-and-dagger, but that's the world we live in.