KINSHASA (AFP) - Deadly violence rocked election day in the Democratic Republic of Congo Monday as polling stations in the giant central African nation came under attack from gunmen and voters angry at long delays. Two policemen and a woman voter were killed and two soldiers were wounded when gunmen staged an assault on a voting station in the flashpoint city of Lubumbashi in the southeast of the country, a military spokesman said. Armed men also swooped on a convoy of jeeps carrying election materials in Lubumbashi, while in the central town of Kananga voters torched a string of polling stations, amid complaints of undelivered ballots and long delays. The run-up to the presidential and parliamentary votes had already been marred by violence pitting supporters of President Joseph Kabila against those of his chief rival, the veteran opposition leader Etienne Tshisekedi. The 40-year-old Kabila, who has been in power since 2001, is tipped to win the single-round poll and secure another five-year term against a divided opposition field of 10 challengers. The elections are just the second since back-to-back wars from 1996 to 2003 in a country that remains one of the world's poorest despite an abundance of cobalt, copper, diamonds and gold. Logistical headaches in organising the vote in a nation two-thirds the size of western Europe -- and whose roads network is crumbling and limited after seven years of war and decades of under-development -- had raised fears the polls could be postponed. In the most serious incident Monday, a military spokesman said two policemen were killed at point blank range and a female voter was hit by a deadly stray bullet in Lubumbashi, DR Congo's second largest city and its mining hub. Some of the attackers were also killed, he said. "I can't say how many, we are collecting the bodies," he said. After the attack, an AFP correspondent saw some 20 soldiers in a line in front of the polling station, armed with a rocket-propelled grenade launcher and automatic weapons. Police also said armed men had swooped on a convoy of eight jeeps in the capital of Katanga province before dawn and fled when police escorting the vehicles opened fire, wounding some of the assailants. Two jeeps carrying nearly 1,000 ballots caught fire, AFP correspondents said. An ex-member of a separatist movement fighting for the restive mining province's independence told AFP the group had carried out the attack. "We want a self-determination referendum, and not this vote that doesn't have anything to do with us in Katanga," the self-described lieutenant Chana Kazi said by phone from South Africa.