Responding to a female fan who asked him to persuade Fox to join Twitter, Monaghan fired off a tweet claiming his former co-star "beats women".
Puzzled sources close to Fox insist the British actor is ill-informed, but Monaghan isn't backing down.
When the fan, named Becca, responded to his comments, writing, "What about all those good times you had together?", Monaghan shot back, "How do you know we ever did? you don't know either of us.he beats women.not isolated incidents.often.not interested."
And the one-sided feud continued on Monday (28May12) as sources close to Fox rallied to dismiss his former co-star's allegations.
Monaghan added, "It's very difficult to sue someone for speaking the truth."
Fox, who hit headlines last year (11) when he was accused of allegedly lashing out at a female bus driver, has yet to comment on the wild claims.