Jan 20 (Reuters) - Myanmar's military has arrested three people working for the independent news portal Dawei Watch, an editor at the publication said on Thursday, the latest detentions under a media crackdown that has occurred since last year's coup.

Moe Myint, a 35-year-old journalist and a mother-of-three, was detained on Tuesday in Dawei, a city in southern Myanmar, said the editor, who asked not to be named due to the sensitivity of the issue.

Another journalist, Ko Zaw, 38, and Thar Gyi, a 21-year-old web designer at the publication, were arrested on Wednesday.

"They are currently being held at a police station in Dawei and the reason for their arrest is still unknown," said the editor, who called for them to be released immediately.

A spokesman for the ruling military junta did not respond to a request for comment.

The junta has previously said it respected the role of the media but would not allow reporting it deemed false or likely to cause public unrest.

The military has rescinded media licences, imposed curbs on internet and satellite broadcasts and arrested dozens of journalists since its Feb.

1 coup.

Myanmar ranked as the world's second-worst jailer of journalists in a report published by the Committee to Protect Journalists.

Reporting ASEAN, a Southeast Asia media advocacy group, said since the coup 115 journalists had been detained and 44 remained in detention and three had died.

Some foreign journalists have also bee detained, including American journalist Danny Fenster website who was the managing editor of independent psihologi online magazine Frontier Myanmar.

Fenster was sentenced to 11 years in prison last November for incitement and violations of laws on immigration and unlawful assembly, before being released following negotiations between former U.S.

diplomat Bill Richardson and the junta. (Reporting by Reuters Staff; Editing by Ed Davies and Alex Richardson)