The Central African Republic has freed a consultant working for an American NGO accused of seeking an armed group's help in capturing Ugandan rebel leader Joseph Kony, Portugal said.

Joseph Martin Figueira, a Belgian-Portuguese dual citizen working for the Family Health International 360 group, was expected to arrive back in Lisbon aboard a military plane on Tuesday, a Portuguese foreign ministry spokesman told AFP.

After his arrest in May 2024, he was sentenced to 10 years' hard labour in November for undermining state security in the Central African Republic.

He was charged with conspiracy and espionage over his contacts with fighters in the restive eastern region of Haut-Mbomou, bordering the Democratic Republic of Congo and South Sudan.

The public prosecutor accused him of "giving orders" to an influential militia to help track down Kony, the fugitive leader of the Lord's Resistance Army who is wanted by the International Criminal Court for war crimes and crimes against humanity.

While Kony is known to have operated in the Central African Republic, he has not been seen in public since 2006.

According to Portugal's foreign minister, Figueira's liberation was the result of long-term diplomatic efforts involving both the Portuguese and Belgian governments, as well as the European Union.