“We can confirm the recent deaths of two U.S. citizens in the Donbas region of Ukraine,” a spokesperson for the department said. “We are in touch with the families and providing all possible consular assistance.”
The State Department declined to provide any further details about the identity of the citizens or the nature of their deaths. It did not say what the men were doing in Ukraine.
“Out of respect to the families during this difficult time, we have nothing further to add,” the State Department said.
At least three other U.S. citizens have died since Russia invaded Ukraine on Feb. 24, two of whom were killed during combat.
Former U.S. Marine Willy Joseph Cancel, 22, was killed in April after agreeing to go to Ukraine as part of his work with a private military contracting company, his mother, Rebecca Cabrera, told CNN at the time. Cancel had gone to Ukraine in mid-March and was survived by his wife and their 7-month-old child, she said.
The following month, Stephen Zabielski, 52, of Hernando, Florida, was killed while fighting in the village of Dorozhniank.
Jim Hill of Idaho, who had been living in Ukraine’s capital, Kyiv, was also killed in March.
The State Department has repeatedly warned U.S. citizens against traveling to Ukraine and said that any U.S. citizens still in Ukraine should leave immediately.
Thousands have lost their lives in the ongoing conflict, according to the United Nations, which said Monday that more than 5,100 civilians had died since late February, more than 340 of whom were children, the U.N. said. The true toll of civilian casualties is, however, believed to be much higher, according to the U.N.
Inside Ukraine, heavy fighting has raged in the country’s south since Thursday, Britain’s defense ministry said in a briefing Saturday.
Ukrainian forces were continuing an offensive against Russia in the Kherson province to the west of the Dnipro River, the ministry said, adding that “supply lines of the Russian forces west of the river are increasingly at risk.”
The briefing came less than 24 hours after the U.S. pledged an additional $270 million of military support for Ukraine, including drones, ammunition and rocket systems.
The White House is also considering whether to send U.S.-made fighter jets to the country.
There have been no significant breakthroughs on the front lines since early July, when Russian forces seized the last two Ukrainian-held cities in the eastern province of Luhansk.
An unknown number of Americans, mostly with military backgrounds, have traveled to Ukraine to join the country’s foreign legion and fight alongside Ukrainian soldiers there.
Veterans from several other countries have also been killed and captured by Russian forces and Moscow-backed separatist forces in eastern Ukraine.
British aid worker Paul Urey, 45, who was accused of being a mercenary, died last week, an official in the self-proclaimed Donetsk People’s Republic said last week. The breakaway entity is recognized only by Russia, Syria and North Korea.
Two Britons and a Moroccan man were sentenced to death last month after they were taken prisoner.
Abigail Williams reported from Washington and Rhoda Kwan from Taipei, Taiwan.
This story first appeared on NBCNews.com.