Protesters and security forces battled in the center of Tripoli as anti-government unrest gripped the Libyan capital, long-time ruler Moammar Gadhafi's stronghold.

A doctor inside the country said six days of anti-government protests -- met by a brutal reaction from government security forces and alleged paid mercenaries -- had left more than 300 people dead.

British oil giant BP said it was "very likely" its staff would be pulled out of the country -- a major petroleum producer - within days as the movement to topple Gadhafi's family from power after four decades appeared to gain steam. BP has about 140 employees in the country, of which less than a third are expatriates, spokesman David Nicholas said. The company is in the early stages of exploration in Libya.