AMSTERDAM (Reuters) - The last two suspects sought by a U.N. tribunal over their alleged role in the 1994 Rwandan genocide died in 1998, the U.N. war crimes prosecutor tasked with finding them said on Wednesday.

The prosecutor said investigations had shown that fugitives "Ryandikayo" and Charles Sikubwabo had both died in 1998, around four years after they had fled Rwanda for what was then Zaire, now Democratic Republic of Congo.

Both had been charged with genocide, and with crimes against humanity including murder and extermination.

In the last four years, the International Residual Mechanism for Criminal Tribunals had already arrested two Rwandan genocide suspects and confirmed the deaths of four other fugitives.

The former U.N. tribunals for war crimes in Rwanda and Yugoslavia have been rolled over into a successor court that has offices in The Hague, Netherlands, and in Arusha, Tanzania.

There already were no remaining fugitives from the Yugoslavia tribunal and now all fugitives for the Rwanda tribunal have also been accounted for, with a number of cases still ongoing.

(Reporting by Bart Meijer; Editing by Alison Williams)