In an effort to disarm the militias at Bani Walid, one of the last major pockets of support for the former Libyan dictator Muammar Gaddafi regime, Libya’s defence ministry readied its forces and allied itself alongside other militias to advance on a town where most of the people are reported to be heavily armed with rocket-propelled grenades, automatic weapons and artillery left over from last year’s eight-month civil war.