Man tweets from outside Rihanna's home, threatens to kill her! See his tweets

A crazy stalker named Ralph Alexander, (pictured left), actually went to Rihanna's home in California earlier today May 1st and took a photo outside her home which he shared on twitter. He then announced that he had a gun and he would use it to murder the pop-star.

After tweeting about it, fans immediately alerted the police but I'm not sure if the man has been arrested. See what he wrote after the cut...