BOGOTA (Reuters) - A nationwide Marxist rebel offensive raged on after dark on Sunday as the government clamped a dusk-to-dawn curfew on one-third of Colombia, including towns around Bogota, for a second night. Guerrillas were still fighting virtually hand to hand with security forces in the streets of at least three communities. Over the last 48 hours, the rebels have bombed 24 towns with missiles made from gas cylinders, have attacked barracks with homemade tanks built from tractors, and have blown up bridges and energy infrastructure. The army branded the "demented terrorist offensive" a failure. The push began 10 days before the Revolutionary Armed Forces of Colombia (FARC) were to restart peace talks with the government. An army statement said 202 guerrillas had been killed, with a loss of just 19 policemen and four soldiers. At least nine civilians were also reported killed. A FARC source, citing a statement from chieftains of the rebels‘ so-called Eastern Bloc division, said 68 security force members had been killed and 32 insurgents died. There was no independent confirmation of the death tolls. Both sides in the conflict routinely minimise their own casualties and exaggerate enemy losses for propaganda purposes in this long-running war, in which more than 35,000 people have been killed in 10 years. The latest clashes have largely been restricted to country towns, and there was no repeat of Thursday‘s intense combat in mountains on the edge of Bogota, in which 78 people died. But authorities warned that the FARC and the smaller National Liberation Army (ELN), which have a combined combat force of 20,000, were planning to storm regional capitals and possibly even Bogota, a city of 7 million people. Military brass and government ministers said the FARC was jockeying for position at peace talks, which are going ahead without a ceasefire, not staging an all-out drive for power. Interior Minister Nestor Humberto Martinez said a curfew prohibiting all road and river travel in 10 of the country‘s 32 provinces and 10 towns just outside Bogota during hours of darkness, would remain in force indefinitely. The latest clashes seem certain to fuel scepticism about President Andres Pastrana‘s plodding peace initiative. The FARC is using a Switzerland-sized safe haven in the southeast, which Pastrana cleared of government troops to make way for peace talks, as a springboard for its raids. In an opinion poll carried out in major cities, 70 percent of respondents said they believed the FARC was a terrorist organisation without ideology, while 61 percent said the group was fighting to achieve economic, not political, goals. But the rebels, who took up arms against the state in the mid-1960s, have active support in the countryside and among the poor in cities, including Bogota.