WASHINGTON — More than a dozen attack jets that Russia sent to Libya this year are conducting ground strikes and other combat missions in support of Russian mercenaries fighting alongside a beleaguered commander in his campaign to oust the government from Tripoli, the capital, a top American military official said on Friday.
The Pentagon’s Africa Command revealed in May the deployment of at least 14 MiG-29 and Su-24 jets to Libya, underscoring Moscow’s deepening role in a sprawling proxy war, where its Libyan ally, the commander Khalifa Hifter, had experienced a series of setbacks that dealt his campaign a major blow.
The planes were flown from Russia to Syria, where their Russian markings were painted over to camouflage their origin, American military officials said. The aircraft were then flown into Libya, in violation of a United Nations arms embargo. At the time, the scope and scale of the aircrafts’ missions were unclear.
Rear Adm. Heidi Berg, the Africa Command’s director of intelligence, said on Friday that the Russian planes, flown by crews from the Wagner Group, a Kremlin-backed private military company whose mercenaries provided a major boost to Mr. Hifter’s assault on Tripoli last fall, had carried out several ground strikes and other missions.
“These fighters are engaging in combat activities,” Admiral Berg said in a telephone interview with reporters. “They’re not there for training.”
But the operations have come at a steep price, Admiral Berg said. Two of the MiG-29’s crashed, one in June and another last week. The cause of the crashes — whether mechanical mishap, pilot error or something else — was unknown, she said, but possibly indicated a lack of technical skill and competence.
Russian military cargo aircraft, including IL-76’s, continue to supply Wagner Group forces operating in Libya with military armored vehicles, SA-22 air defenses systems, fuel, ammunition and other supplies, further increasing the risk for miscalculation and continued violence in Libya, she said. While Moscow reportedly wants to install sophisticated S-300 or S-400 air defenses in Libya, Admiral Berg said that had not yet happened.
The vast scale of secret, embargo-busting arms flights by Russian and the United Arab Emirates to support Mr. Hifter was revealed in a confidential report presented this month to a panel of the United Nations Security Council, and viewed by The New York Times.
Libya descended into chaos in 2011 after the ouster and killing of the longtime ruler Col. Muammar el-Qaddafi. Since then it has been divided between two administrations, in the east and west of the country, backed by rival foreign powers.
A 14-month campaign by Mr. Hifter to capture Tripoli ended in failure in June but drew Russia and Turkey more deeply into the war.
Russia’s Wagner group now has 3,000 personnel and 2,000 Syrian mercenaries on the ground in Libya, Admiral Berg said, while Turkey has 5,000 Syrian mercenaries of its own as well as several hundred Turkish troops in the country. Russia has repeatedly denied any intervention in Libya.
There is no evidence so far that the Islamic State has seeded large number of operatives in the mercenary ranks, Admiral Berg said.
The Africa Command has over the past several months issued a series of news releases condemning Russia’s involvement in Libya, often including satellite imagery of Russian aircraft as well as the Wagner forces and equipment on the front lines of the Libyan conflict in Surt.
American military officials say that the Wagner Group has laid land mines and improvised explosive devices, or I.E.D.s, in civilian areas in and around Tripoli jeopardizing the safety of civilians. The Africa Command says the satellite imagery also shows that Wagner Group transport trucks and Russian mine-resistant, armored vehicles are also present in Libya.
Russia is steadily expanding its military influence across Africa by increasing arms sales, security agreements and training programs for unstable countries or autocratic leaders. Other recent actions by Moscow include quietly deploying mercenaries and political advisers to several countries, including Mozambique and the Central African Republic.
American officials, analyzing what they call great power competition, say they are alarmed by Russia’s growing influence, as well as China’s, as Washington struggles to exert its economic and security goals on the continent.