Tripoli, Aug 1 (IANS): The UN has demanded the immediate release of Ismail Abuzreiba, a Libyan journalist sentenced to 15 years in prison by a military tribunal in the eastern city of Benghazi.

In a statement late Friday, the US Support Mission in Libya (UNSMIL) said that it was dismayed by the sentencing of the journalist, calling for his immediate release, reports Xinhua news agency.

"The Mission is concerned that the detention and trial appear to violate Libya's laws as well as its international obligations," the statement said.

Abuzreiba is known for opposing the eastern-based army, which controls eastern Libya.

The eastern-based authorities of Libya have not announced the reasons for Abuzreiba's arrest yet.

Libya has been engaged in a civil war since the ouster and killing of former leader Muammar Gaddafi in 2011.

The situation escalated in 2014, splitting power between two rivals with warring forces -- the UN-backed Government of National Accord (GNA) based in the capital Tripoli and the eastern-based Libyan National Army (LNA) led by Khalifa Haftar.

Egypt, Russia and the United Arab Emirates support Haftar's LNA, while the GNA is mainly backed by Turkey and Qatar.