An international media rights group says an Eritrean government journalist has disappeared within the country's jail system after being held for two years without trial.

Reporters Without Borders, citing local sources, says Eritrean authorities had been holding Tura Kubaba since his arrest in 2006. The group says it only recently learned that authorities transferred Kubaba to an unknown location last year.

The rights group says Kubaba worked for the Kunama-language service of the state-run Radio Dimtsi Hafash. It says authorities arrested him on charges of associating with ethnic Kunama opposition groups.

The group has called on the government to stop "hindering" cases such as Kubaba's from coming to light.

There was no independent confirmation of the group's claim.

Earlier this year, Reporters Without Borders cited Eritrea as one of the worst places for press freedom in Africa. In an annual report released in February, the group said the few independent journalists in the country were arrested in 2001 and are still detained in secret.

Eritrea's government has denied the country lacks freedom of the press.