GENEVA (Reuters) - The United Nations condemned a   coordinated series of attacks  on Myanmar security forces on Friday and called on all sides in the crisis in the northern state of Rakhine to refrain from violence. At least 21 insurgents and 11 members of the security forces were killed in the troubled Rakhine state on Friday when militants staged a major coordinated attack on 24 police posts and an army base, the military said. The statement, issued by the U.N. resident coordinator in Myanmar, Renata Lok-Dessallien, and read out to a Geneva news briefing, urged  all parties to refrain from violence, protect civilians and restore order .  We are deeply concerned about the security situation in Rakhine state,  she added.  