BEIJING, Apr. 24 (AP) -- Unidentified gunmen have attacked a Chinese oil company's field in Ethiopia, China's state-run Xinhua News Agency reported Tuesday.

A Chinese Embassy official in Ethiopia's capital, Addis Ababa, said there were casualties but had no further details, Xinhua said.

China has increased its presence in Africa in recent years, including in areas seen as politically unstable, in a hunt for oil and other natural resources to feed its rapidly growing economy.

The Xinhua report said the oil field was in Somalia state, one of nine states making up Ethiopia.

Ethiopia is heavily involved in the violence in the neighboring country of Somalia, where Ethiopian troops are backing government forces in a fight with Islamic insurgents.

Chinese oil workers have also been targeted in Nigeria by armed militants seeking a greater share of that country's oil wealth. Hostages are normally released unharmed after a ransom is paid.

In March, two Chinese workers were kidnapped in Nigeria. In January, nine Chinese oil workers were taken when gunmen stormed the government-owned Chinese National Petroleum Co. office in Nigeria's state of Bayelsa.

In another incident in southern Nigeria's Rivers state the same month, five Chinese telecommunication workers were kidnapped and safely returned within two weeks.