Stockholm  - Five Swedish editors-in-chief Friday launched a joint petition demanding the release of a jailed Swedish-Eritrean journalist held in Eritrea.

"Dawit Isaak has today been jailed for 2,742 days. Without charge and without any sentence," the editors said in their appeal.

Isaak was apparently jailed over writing and publishing articles calling for "democracy and freedom in Eritrea," they said, noting that Isaak's arrest on September 23, 2001, coincided with the Eritrean government's moves to shut down independent newspapers.

"The regime in Eritrea has never formulated any allegations against Isaak, let alone a prosecution, a trial or a sentence," the editors of the dailies Aftonbladet, Expressen, Dagens Nyheter and Svenska Dagbladet and the online edition of Aftonbladet added.

The editors invited readers to sign a petition due to be presented to the Eritrean embassy on May 4.

Isaak became a Swedish citizen in 1992 after seeking asylum in 1987. Isaak lived in the west coast city of Gothenburg until 2000 when he returned to Eritrea to work for the independent weekly Setit.

The editors also urged Swedish authorities to "start working actively" for Isaak's release, saying it was time to end the so- called "quiet diplomacy" that has been deployed so far.

In March 2007, Isaak was awarded a newly created freedom of speech prize by the Swedish Association of Publicists, but was unable to attend the award ceremony in Stockholm.

His wife and three children, who remained in Sweden, accepted it on his behalf.

Human rights advocacy groups like Amnesty International, Reporters Without Borders and the Swedish Journalists' Union have also campaigned for Isaak's release. (dpa)