(Adds more information on nationality) By Austin Ekeinde PORT HARCOURT, Nigeria, May 6 (Reuters) - Gunmen have kidnapped a Belarussian woman working as an oil industry contractor in Nigeria, bringing the total number of abductions in Africa's top oil producer to 28 in five days. The seizure on Saturday night was the latest in a string of attacks on the Western-operated oil industry in Nigeria, the world's eighth largest crude exporter, which has cut output by a quarter. The woman, a senior manager with the Nigerian unit of British services company Compass Group <CPG.L>, is a Belarussian national who also holds a Nigerian passport, authorities said. Security sources had earlier identified her as Russian. "At 2030 local time (1930 GMT) an employee of Compass Group Nigeria was abducted," said Chris King, spokesman for Compass Group in London. He added he was particularly concerned for the wellbeing of the woman, snatched from the exclusive GRA district of oil capital Port Harcourt, because she required regular medication. Viktor Goncharov, counsellor at Russia's embassy which handles Belarussian interests in Nigeria, said in an interview on Russia's Vesti-24 television channel that the abducted woman was a Belarussian mother of four married to a Nigerian. Earlier on Saturday, armed men boarded a U.S.-operated offshore drilling rig and kidnapped a British worker. Militants released eight hostages last week but 20 foreign workers are stll being held. RESENTMENT There is widespread resentment against the oil industry in the Niger Delta, a vast wetlands region home to all Nigeria's crude. Most deltans live in poverty, with little or no access to electricity, schools or clean water, despite the riches being pumped from their ancestral land. About 100 foreign workers have been kidnapped since the beginning of the year, and most have been released after their employers illegally paid ransoms. Militants fighting for more autonomy in the delta have stepped up attacks against the industry, but the line between militancy and crime is blurred and most abductions are motivated by groups seeking ransom. The frequency of kidnapping subsided in April, when Nigeria held general elections, but has intensified dramatically this month. "Maybe the boys were on holiday and now they have resumed work," said Chris Alagoa of the Niger Delta Peace and Security Secretariat. "They are angry and their anger has not been assuaged because no dividends have been delivered to the Niger Delta people." Some members of a group of 11 Filipinos and Koreans seized on Tuesday have made phone calls home to their families, media in the Philippines reported on Sunday. One of the hostages told his wife his captors had demanded $1 million for their release, ABS-CBN news reported. Hostages are normally released unharmed, although a few have been killed by Nigerian troops in clumsy rescue attempts. Thousands of foreign oil workers have fled Nigeria since a string of militant attacks in February 2006 that reduced output by 600,000 barrels per day, or one fifth of total capacity. Another 65,000 barrels per day were shut off by two attacks on Tuesday and Thursday.
