(Adds another kidnapping and release in paragraph 3) By Tume Ahemba LAGOS, June 3 (Reuters) - Gunmen kidnapped six Russians and shot dead a local driver in a dawn attack on a residential compound of a Russian aluminium company in Nigeria on Sunday, authorities said. The abductions took to 30 the number of foreigners being held by different armed groups in the lawless southern delta, where the kidnapping of expatriates has become an almost daily occurrence. In a separate attack on Sunday, gunmen seized two Filipino workers in the Onne port district but troops fought them, killing one kidnapper, and freed the two captives, military and security sources said. Russia's ambassador to Nigeria, Igor Melikhov, said the six Russians were abducted by gunmen who stormed the residential compound in the southeastern town of Ikot Abasi in two minivans. The identity of the kidnappers and their demands were not immediately known. The Russians were working at the Aluminium Smelter Company of Nigeria (ALSCON), which is controlled by Russia's United Company RUSAL, the world's largest aluminium producer. "A group of militants attacked a residential community of UC RUSAL's employees. Six people have been kidnapped. The driver, who worked for ALSCON, was shot dead," RUSAL spokeswoman Vera Kurochkina said in a statement, adding the company was working to free the hostages. Security sources working for foreign firms said the militants used explosives to gain access to the apartment where the Russians lived. "We are very worried by events happening in Nigeria," Russian Foreign Ministry spokesman Mikhail Kamynin was quoted by the RIA news agency as saying. THOUSANDS FLEE Insecurity in the Niger Delta, home to Africa's largest oil industry, has forced thousands of foreign workers to flee and cut output by a third in the world's eighth biggest exporter. RUSAL acquired a controlling stake in the ailing aluminium plant in 2005 and said in February it would restart the 193,000 tonnes a year smelter by December after investing $150 million. Militants demanding regional control over the delta's resource wealth have stepped up attacks on oil facilities and kidnappings of foreigners since last year, but most abductions are by groups seeking ransoms. In neighbouring Rivers state, gunmen disguised as riot police seized four foreign workers on Saturday from the residential compound of oil services firm Schlumberger in the oil city of Port Harcourt. The unrest is fuelled by a complex set of factors including poverty, lack of basic infrastructure, corruption among government officials and security forces and political thuggery. Hostages are almost always treated well and freed unharmed after some days in captivity, though a few have been killed by Nigerian troops in clumsy rescue attempts. The crisis in the delta has escalated in the last few weeks as President Umaru Yar'Adua took over from Olusegun Obasanjo. In his inaugural address on Tuesday, Yar'Adua promised to give the delta his urgent attention and called for an end to violence. The rebel Movement for the Emancipation of the Niger Delta, which has emerged at the head of the militancy, said on Saturday it would desist from further attacks on oil facilities for a month to allow for dialogue. (Additional reporting by Tom Ashby in Lagos and Gleb Bryanski in Moscow)
