KANO, Nigeria (Reuters) -- A Ukrainian cargo plane bound for Equatorial Guinea has been impounded in Nigeria after security officers found weapons and ammunition on board, a Nigerian official and Ukrainian media said.
The official at northern Nigeria's Kano airport, who asked not to be named, said the plane had stopped to refuel late on June 17 when the arms were discovered during a routine search.
Nigerian police confirmed that an aircraft had been detained but gave no details on its origin or destination.
"I can confirm that the plane was impounded because of the arms found in it. I think it was in transit. Investigations have commenced and we will get a clear picture soon," Nigerian police spokesman Emmanuel Ojukwu told Reuters from the capital Abuja.
The Interfax Ukraine news agency said the plane was an AN-12 cargo aircraft belonging to a Ukrainian company.
A second Ukrainian news agency, UNIAN, quoted the country's main arms export agency Ukrspetsexport as saying the plane's cargo had nothing to do with Ukraine but belonged to Croatia.
The Ukrainian Embassy in Nigeria declined to comment.
Equatorial Guinea, sub-Saharan Africa's third-biggest oil producer and a magnet for U.S. oil companies, has suffered decades of instability.
In 2004 dozens of foreign mercenaries, mostly South Africans, were caught trying to overthrow the president of the tiny former Spanish colony.
The coup attempt caught world attention as it was led by a former British special forces officer and self-confessed mercenary who accused Mark Thatcher, son of former British Prime Minister Margaret Thatcher, of involvement.
Thatcher denied any role.
Gunmen believed to be from Nigeria's Niger Delta, where militants have been staging attacks against oil industry facilities for years, were accused of mounting an attack on Equatorial Guinea's presidential palace in February.
Gunmen in motor boats on Feb. 17 attacked the island capital Malabo before being repelled by the armed forces. Equatorial Guinea's President Teodoro Obiang Nguema Mbasogo fired three senior security and defence officials following the incident.