BANGUI, Central African Republic — The dealer pulled back a shiny pink curtain and sprinkled the contents of two white envelopes across his desk: sparkling diamonds, more than 100 of them.
Some gems are sold legally, he explained. But many are trafficked by rebels who fight over the mines, adding fuel to a six-year uprising that has killed thousands and displaced more than a million people here in the Central African Republic.
Now, hoping to wrest control over the diamond trade and piece the country back together, the government has turned to a new partner — Russia — in what some lawmakers fear is a dangerous bargain that trades one threat for another.
And the central figure behind the Russian involvement, according to local and Western officials, is Yevgeny V. Prigozhin, a confidant of President Vladimir V. Putin who was indicted in the United States last year, accused of helping to finance “information warfare” and disrupt the 2016 American election.
The Central African government has welcomed the Russians, betting that stability will enable it to sell more diamonds legally and use the money to rebuild the nation.
“The rebellion in our country has cost us a lot,” said Albert Yaloke Mokpeme, the spokesman for the Central African president. “No one came to our aid except the Russian Federation.”
“With the help of Russia,” he added, “we will be able to secure our diamond mines.”
The diamond merchant, Arab Arab Koussay, who runs one of the country’s largest dealerships, fingered the gems on his desk and expressed a similar view. “We can’t control everything in this country,” he said.
But Russia’s help comes at a cost. Its representatives have struck deals with the government to mine diamonds where the trade is legal — one of many signs that Russia’s push into the country is closely tied to the profits it can reap.
Russian operatives have even partnered with murderous rebels to obtain diamonds in areas where the trade is outlawed, cashing in on the very lawlessness they have been brought in to end, according to members of the Central African government, Western officials and some of the warlords themselves.
More broadly, the fact that Russian mercenaries are training the nation’s troops has unnerved some lawmakers. Human rights violations in the country are so common that the United Nations imposed an arms embargo against Central African soldiers. But the Russian trainers have been accused of abuses as well, including rounding up innocent bystanders in mass sweeps.
“I keep thinking of what kind of army we are going to have if they are trained by Russians,” said Hamadou Aboubakar Kabirou, a member of Parliament.
Mr. Prigozhin has ties to mining, security and logistics companies that have been set up in the nation since 2017, according to American intelligence officials, Western diplomats and a security analyst who provided registration documents connecting him to some of the businesses. Mr. Prigozhin also personally showed up for peace talks with rebel groups several months ago, according to one warlord present.