(Updates with 2nd incident) March 23 (Reuters) - Gunmen kidnapped three foreign workers in two separate incidents in Nigeria's oil producing delta on Friday, authorities said. A wave of recent attacks led to a 20 percent cut in Nigeria's oil production. Output has yet to recover. Following is a chronology of some major attacks and kidnappings involving the Nigerian oil industry this year. Jan. 12, 2007 - Nine South Korean workers and one Nigerian are freed after being kidnapped when gunmen attacked a base operated by South Korea's Daewoo Engineering and Construction <047040.KS> in the Bayelsa state capital, Yenagoa, on Jan. 10. -- Jan. 16 - Three people, including a Dutch oil worker, are killed when their boat, operated by South Korean firm Hyundai <HYGR.UL>, is attacked on the way to Bonny Island terminal. -- Jan. 18 - Gunmen free five Chinese telecom workers, kidnapped on Jan. 5 in Rivers State. One Italian is released in Bayelsa state. Three foreigners remain in captivity. -- Jan. 23 - Gunmen kidnap two engineers, one American and one British, in the southern oil city of Port Harcourt. The Briton is released on Feb. 7 and the American on Feb 17. -- Jan. 27 - A Belgian man working for a building company dies of wounds after an ambush in Warri in the western Delta. -- Feb. 4 - Nine men working for the Chinese National Petroleum Company (CNPC), which was doing work for Shell in Bayelsa state, are released. They were kidnapped on Jan. 25. Feb. 7 - A Frenchman, working on contract for oil giant Total <TOTF.PA>, is kidnapped in Port Harcourt. -- Feb. 13 - Militants release all 24 Filipino crew members, who were captured when their cargo ship, belonging to German line Baco-Liner, was attacked on Jan. 20. -- Feb. 23 - Gunmen kill a Lebanese construction engineer in Port Harcourt. -- Feb. 26 - Two Italians, working for construction company Impregilo <IPGI.MI> are released. They were kidnapped near Port Harcourt on Feb. 23. -- Feb. 28 - Gunmen kidnap a Lebanese construction worker at Mbiama community in Rivers state. He was employed by Alren Construction Nigeria Ltd. He is released three days later. -- March 8 - A Filipino worker, kidnapped on the road between Port Harcourt and Owerri on Feb. 6, is released. -- March 12 - Troops rescue two Croats and one Montenegrin, employees of Hydrodrive Nigeria, who were kidnapped on Feb. 18 by suspected ransom-seekers in Port Harcourt. -- March 15 - Two remaining Italians, Francesco Arena and Cosma Russo, kidnapped from the Agip oil export terminal in Bayelsa state on Dec. 7, 2006, are released. The Movement for the Emancipation of the Niger Delta claimed responsibility. March 23 - Gunmen kidnap the Dutch security manager of German construction company Bilfinger Berger <GBFG.DE> in Port Harcourt. -- In Warri, unidentified gunmen take two foreign staff of Nigerian construction firm Setraco from their workplace. The hostages include a Lebanese national and possibly an Indian.
