The U.N. peacekeeping chief said today that U.N. military observers in Syria are reporting cease-fire violations from the government and opposition and he demanded an immediate halt to all violence.Twenty-four observers were in Syria on Tuesday in five locations: Damascus, Homs, Hams, Daraa and Idlib-- all hotspots in the 13-month uprising that by U.N. account has killed more than 9,000 people, UN Peacekeeping chief Ladsous said at a news conference.