Robert Plant has recently had to take some safety precautions, including obtaining a restraining order against a woman he claims is stalking him.

TMZ reports that the Led Zeppelin vocalist says that Alysson Billings has been harassing him for the past three years, believing that she is involved in a relationship with the singer even though the two have never met. Plant says Billings sends him flowers and random packages, leaves him hotel keys and also shows up to his concerts in various places all over the world.

Disturbingly, Plant says that since he publicly started dating Patty Griffin, BIllings' messages to him have taken a much darker tone. She has told Plant, "Your betrayal with another woman still stabs my mind", and "She's got you so p---y whooped and henpecked, it makes me want to puke ... and I'm telling you that rotten crotch is ruining you."

Perhaps the most disturbing message of all from Billings to Plant is this one: "This woman is literally evil for you and your life ... you are about to fall for that dirty old crotch. And I'm not joking, I cannot, will not, shall not live this way anymore."

Needless to say, Plant is taking these threats very seriously, having gone to the extreme of hiring a security assessment team -- who apparently agreed that Billings poses a danger to him.

Updated 5/22: According to TMZ, Plant has been granted a restraining order requiring Billings to stay 300 yards away from the singer at all times for the next three years.