BBC NEWS / AFRICA
Four people who were plotting to sabotage one of the largest hydro-electric dams in Africa have been arrested in Mozambique, police say.
The detained were foreigners caught with materials designed to damage the Cahora Bassa dam in north-western Mozambique, according to state media.
The suspects were from South Africa, Botswana, Germany and Portugual, police reportedly said.
The accused allegedly tried to put a corrosive chemical in the dam turbines.
National police spokesperson Pedro Cossa told a weekly briefing in Mozambique's capital, Maputo, that 1,100lb (500kg) of the unidentified corrosive substance had been confiscated, reported the South African Press Association.
"The suspects were caught putting the substance into the dam's turbines," Mr Cossa was quoted as saying by Sapa.
The Cahora Bassa dam, on the Zambezi River, is a vital source of electricity for Mozambique, South Africa and Zimbabwe.
Built in 1974 when Mozambique was still a Portuguese territory, ownership of the dam transferred two years ago to the Mozambican government.
Mozambique is among African countries which have pledged to provide electricity to South Africa during next year's World Cup to prevent power cuts.