"I confirm that we have detained a Russian 'Ruslan' cargo Plane which is carrying six jet fighters for Yugoslavia," Vafa Guluzade, AN adviser to President Haydar Aliyev, told Reuters.
Moscow denied that the Plane was on its way to Yugoslavia in breach of the international arms embargo and demanded its release.
Russian Foreign Ministry spokesman Vladimir Rakhmanin said the AN-124 cargo Plane was flown by a private Russian carrier, but its cargo belonged to the former Soviet republic of Kazakstan And was bound for Bratislava, Slovakia.
The AN-124 arrived in Azerbaijan's capital on Thursday for refueling, according to the Azerbaijani Turan news agency.
Customs agents prevented the Plane from leaving after finding six jet fighters and other military hardware on board, along with about 30 pilots and technicians, the report said.
Officials with Azerbaijani Airlines, the state-run carrier, said the plane's flight plan originally listed its destination as the North Korean capital of Pyongyang.
The destination was changed to Bratislava today, the ITAR-Tass news agency reported. No explanation was given for the change.
The Russian Embassy in Baku protested the plane's detention, saying the AN-124 carried six disassembled MiG-21 fighters owned by the Czech company Agroplast and bound for Bratislava.
Azerbaijani officials have detained 34 people aboard the Plane, including Russians, two Kazaks, one Ukrainian And one Belarusian, ITAR-Tass reported.
Russian officials said the Plane was detained for "unknown reasons" on the night of March 19-20, not on March 18 as the reports in Azerbaijan said.
Authorities in Kazakstan refused to comment on the Plane, but the Interfax news agency quoted local officials as saying the aircraft flew to Baku from Taldy-Kurgan in southern Kazakstan.
They refused to give further details.
In Bratislava, spokesmen at Slovakia's Defense Ministry said they were not aware of any planned MiG deliveries.
The Russian Defense Ministry in Moscow said it was not involved with the aircraft in any way.