
Assaf Cohen will be playing a villain in the double-hour episode (15/16) next week (April 5th).
On March 22, 2010, Assaf will Guest Star as a murder suspect on CSI: MIAMI. Two weeks later, on April 5th, Assaf returns to FOX’s “24″ as a bad guy!
He previously played the terrorist “Yassir” who worked under Habib Marwan in 24 Season 4.
Source: Official Assaf Cohen website

The role of Mehran has been cast, with Mido Hamada nabbing the part.
Mido Hamada has booked a recurring role on Fox’s “24″ playing Mehran, the leader of a group of operatives in an Islamic country working against their president. Mido has appeared on “Path to 9/11″ and was a series regular on “State of Mind.” He is repped by Laina Cohn Management, Patrick Hambleton Associates and John Meigs.
Source: The Hollywood Reporter
Here was last months casting call for this character:
MEHRAN – Middle Eastern, in his mid 20s to mid 40s, he is the leader of operatives in an Islamic country working against the President (Anil Kapoor). Mehran is very charismatic but dangerous. Introduced in one scene in Episode 8, this character will be in multiple episodes… GUEST STAR.
ALI – Middle Eastern in his late 20’s to early 40’s, he is the right hand Lieutenant to the head of the opposition to President Hassan (Anil Kapoor). Ali believes in the cause and has no problem killing or being killed to accomplish it for his boss, Samir. Will be in several episodes.
Source: SpoilerTV

William Keck from TV Guide Magazine has wrangled a little more information out of 24 writer Brannon Braga regarding Callum Keith Rennie’s character:
Battlestar Galactica vet Callum Keith Rennie, who played Leoben Conoy on the sci-fi series, will be joining his former co-star Katee Sackoff on the new season of 24, premiering in January 2010. Callum, who also had a recurring role on Californication and played Harper’s Island killer John Wakefield, will be playing Vladimir Laitanan. Co-executive producer Brannon Braga describes the character as a Russian syndicate mobster who debuts around episode six or seven. “We love this actor,” says Braga.
Expect Vlad to team in some way with 24‘s other new villain, Eastern European mobster Bazhaev, played by “Das Boot” actor Jurgen Prochnow.
Source: TV Guide Magazine

IMDB is now listing Jordan Marder under the role of Dimitri. Here is the casting call for Dimitri as a refresher:
DIMITRI – Eastern European, in his mid 30s to mid 40s, he is an enforcer for our “European Godfather.” Dimitri is introduced in Episode 5 and will return in Episode 8 where he has an intense encounter with Jack Bauer. Cannot be any taller than 5’11” and should have a slight Eastern European accent.. GUEST STAR.
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