Russia’s Foreign Ministry said on Friday a preliminary investigation showed three Russian journalists were killed in the Central African Republic this week by assailants who wanted to rob them.

The three journalists, whose employer said they were investigating Russian mercenaries in the torn country, tried to resist their attackers when they were killed, spokeswoman Maria Zakharova said at a briefing in Moscow on Friday.

Reporters Without Borders (RSF), a journalism advocacy group, said given the volatility of the country, it was plausible that the journalists had been victims of a financially motivated attack - although other motives were possible.

“We know there is a strong Russian presence in Central Africa and to what extent this investigation on Russian mercenaries, an investigation which was being led by these three Russian journalists, could have been causing problems, it’s a question which can be asked,” said Arnaud Froger, an RSF member in charge of Africa.

“At this time, no lead should be ignored including that of a targeted hit,” Froger said.

Orhan Dzhemal, Alexander Rastorguyev and Kirill Radchenko were working for TsUR, which is financed by Kremlin critic Khodorkovsky, when they were ambushed on Monday. 

Central African Republic has been ravaged by violence since a 2013 rebellion overthrew then-President Francois Bozize.

But the zone where the men were ambushed is patrolled by armed forces in collaboration with a U.N. mission and has not been the site of serious recent incidents, the mission said.

The group had $8,500 in cash with them and expensive equipment including two video cameras, she was quoted as saying.