Pro-Gaddafi troops have launched a fresh attack on the rebel-held city of Misrata in western Libya. A BBC correspondent in the city said there had been rocket attacks. A spokesman for the rebels said 12 of their fighters had been killed. Misrata has suffered heavy shelling since the conflict began in February. The latest attack came as Nato intensified its campaign in Libya, and called for the international community to prepare for a post-Gaddafi era. Rebel spokesman Hassan al-Misrati told Reuters news agency from inside the city: "Gaddafi forces are shelling Misrata from three sides. "He has sent thousands of troops from all sides and they are trying to enter the city." Misrata suffered intense bombardment until mid-May, when pro-Gaddafi forces were driven away from central parts of the port city. The government has so far not commented on the latest attack. Meanwhile, Nato ministers met in Brussels on Wednesday to discuss the alliance's nine-week campaign. Afterwards, Secretary General Anders Fogh Rasmussen told reporters that "real progress" had been made. Nato action, he said, had "prevented a massacre" in Benghazi in the east - the rebels' stronghold - and in Misrata. He added that the UN and other international bodies should start preparing for a post-Gaddafi Libya. "The time to start planning is now," he said. Source: BBC