Former Brazilian model Thalita do Valle who fought with Ukrainian troops together with her brother was killed during the Russian bombing in Kharkiv.
The family - reports the Dayly Mail - has announced that the 39-year-old died of asphyxiation after being trapped in a bunker on fire from the explosions.
Do Valle previously fought with Kurdish forces against Isis in Iraq.
"There were Russian attacks and the battalion was divided. Thalita took refuge in the bunker, died on June 30 of asphyxiation, was not hit by shrapnel," said brother Theo Rodrigo Vieira, adding that his sister was sending messages. from the front practically every day, she worked both as a rescuer and as a sharpshooter.
She was also responsible for providing cover from advancing Russian forces.
Do Valle had been a model as a young man before studying law.
She then she worked with charities, later she joined the Kurdish Peshmerga forces in Iraq where she was trained as a marksman.
Vieira said her sister had arrived in Ukraine three weeks ago before being sent to the city of Kharkiv, which is no longer under direct Russian attack but is still frequently bombed from across the border.