Human-rights activists said Sunday that at least 25 people had been killed Sunday in a deadly crackdown in the northern port city of Latakia. Witnesses said that Syrian tanks and, for the first time, naval ships, mounted with machine guns, fired at citizens in a residential neighborhood. The Syrian government reportedly imposed a curfew on Latakia and the surrounding suburbs. “Anyone who sticks his head out the window risks being shot,” one witness reported. Sunday’s deadly crackdown came after five were killed Saturday in Latakia, Syria’s main port city. Meanwhile, security forces “launched a campaign of arrests” in the neighborhoods of Saqba and Hamriya around the capital, Damascus, said a British human-rights agency.