Fierce fighting continues for the centre of Misurata, the only significant western Libyan city in the hands of the opposition. br br Forces loyal to Libyan leader Muammar Gaddafi have been pounding it with shells and rockets in recent weeks.br br But rebel fighters say they are making gains, according to footage from an organisation connected to the National Transitional Council.br br Al Jazeera's Nick Toksvig reports.