The flights were permitted by the United Nations Security Council, which waived an arms embargo on the conflict-ridden country to allow its armed forces to better equip themselves.
At the same time, 175 military trainers -- all but a handful of them private contractors -- arrived from Russia.
In turn, those trainers were followed by Russian companies eager to exploit the Republic's reputed mineral wealth.
The activities of those firms, which have ties to the inner circle of Russian President Vladimir Putin, were the target of three independent Russian journalists who were killed in CAR on Sunday
: Kirill Radchenko, Alexander Rastorguyev and Orkhan Dzhemal.
Their trip was backed by a foundation -- the Center for Investigation -- run by Russian exile Mikhail Khodorkovsky. A long-time foe of Putin who spent years in prison in Russia, Khodorkovsky wrote on Facebook Wednesday that the journalists were working on a project about "Russian mercenaries."
The deaths of the journalists have focused attention on Russia's growing interest in central Africa, and the relationship between the Kremlin and private Russian companies that combine security work with mining and other activities.
An ill-fated journey
The three men had traveled via Morocco on tourist visas, informing neither the Russian embassy nor CAR authorities of their presence because they wanted to investigate the activities of a Russian military contractor called PMC Wagner, the Center for Investigation said.
Perhaps not surprisingly, the journalists were refused permission to visit a site south of Bangui, where Russian trainers are based at a crumbling palace that belonged to the former ruler of CAR, Jean Bedel Bokassa. Adjacent to the palace is a long runway.