A screen grab of the redirected Twitter site last night
A group calling itself the Iranian Cyber Army hacked into Twitter  for nearly two hours last night, replacing it with an anti-American message. An Iranian opposition website, mowjcamp.org , was also hacked into, with some disruption continuing today.
In broken English, the hackers claimed on Twitter that they had turned the tables on America, which they criticise for imposing sanctions on Iran:
U.S.A. Think They Controlling And Managing Internet By Their Access, But They Don't, We Control And Manage Internet By Our Power, So Do Not Try To Stimulation Iranian Peoples To . . .. NOW WHICH COUNTRY IN EMBARGO LIST? IRAN? USA? WE PUSH THEM IN EMBARGO LIST ;) Take Care.
(I just love the winky face -- and the polite signoff. "Take Care", much love, from Cyber Army.)
But, on a more serious note, this is a very political statement. Both websites have been a focal point for pro-democracy protesters over the past few months. Twitter in particular has been used to spectacular effect to disseminate information  about demonstrations in Iran across the world, after stringent restrictions on foreign media reporting.
The text on the Mowjcamp.org website was different, with one part reading  (in Persian):
If the leader orders us to, we will attack and if he wants us to, we will lose our heads. If he wants us to have patience and wait, we shall sit down and put up with it.
Is the conservative backlash against the ongoing unrest in Iran starting in earnest?