More details emerge:
Unlike the other protesters reported killed on Sunday, Ali Moussavi appears to have been assassinated in a political gesture aimed at his uncle, according to Mohsen Makhmalbaf, an opposition figure based in Paris with close ties to the Moussavi family. Mr. Moussavi was first run over by a sport utility vehicle outside his home, Mr. Makhmalbaf wrote on his Web site. Five men then emerged from the car, and one of them shot Mr. Moussavi. Government officials took the body late Sunday and warned the family not to hold a funeral, Mr. Makhmalbaf wrote.
Juan Cole adds some punch to what we already know about Ali:
Killing a sayyid is a blot on any Iranian government. Doing so on Ashura, the day of morning for the martyred grandson of the Prophet, Imam Husayn, borders on insanity.