Five European citizens, including three Britons, captured in eastern Ukraine have gone on trial in a court administered by Kremlin-backed separatists in the city of Donetsk, Russian media reported.

The five — including Swede Matthias Gustafsson, Croat Vjekoslav Prebeg, and Britons John Harding, Andrew Hill and Dylan Healy — all pleaded not guilty to charges of mercenarism and “undergoing training to seize power by force”, according to Russian media.

They could face the death penalty under the laws of the self-proclaimed, unrecognised Donetsk People’s Republic.

The next court hearing in their case is scheduled for October, the Interfax news agency reported, citing a statement by the separatists’ court.

On June 9, the supreme court of the self-proclaimed republic sentenced two Britons and a Moroccan, all of whom were captured by pro-Russian forces in Ukraine’s industrial east, to death for being mercenaries.

All three have appealed against their verdicts.

Ukrainian social media has been speculating that the Kremlin may seek to use the foreign fighters to extract concessions from Ukraine or swap them for Russian prisoners.