Ukraine war: Actor Sean Penn walks miles on foot to Polish border to flee Ukraine

Among thousands fleeing war zones in Ukraine amid Russian invasion was Hollywood actor-director Sean Penn.

Days after visiting the Ukrainian capital Kyiv to film scenes for his documentary on Russia's invasion, Sean Penn has now evacuated to Poland, as the crisis between Russia and Ukraine intensifies.

On Monday, the Academy Award-winning actor took to Twitter and posted a photo of himself wearing a backpack and carrying his luggage on wheels as he trudged along a road beside a line of cars.

In the tweet, Penn said that he and two of his colleagues had to abandon their vehicle and walk miles to the Polish border to exit the war-torn country.

Penn had been filming a documentary about the escalating conflict between Russia and Ukraine since November of last year. He was earlier seen wearing a military helmet and vest as he toured many places, and interacted with Ukrainian soldiers, while his crew captured everything on camera.

Penn had interviewed Ukrainian political and military figures as well as journalists as part of the production, for which he initially visited Ukraine in November.

Also Watch | Ukraine: Hollywood star in Kyiv to record war for documentary, thanked by Zelenskyy govt | Sean Penn

Penn, whose directorial credits include 'Into the Wild' and 'The Crossing Guard', is also known for his political activism and involvement in various humanitarian causes, including relief efforts for victims of Hurricane Katrina, the Haiti earthquake of 2010 and Pakistan floods in 2012.