Maksim Chmerkovskiy shares 'traumatizing' escape from Ukraine amid Russia invasion

Maksim Chmerkovskiy is on a train to Poland after fleeing Ukraine on Monday. The Dancing With the Stars pro has been detailing his experience in his birth country amid Russia's invasion, telling his 1 million followers "the situation at the train station is insane."

"AT first it feels manageable, but it gets A LOT worse when it comes time to actually board the train. Long story but all I can say now is that I'm a big man with nothing but a backpack it's TRAUMATIZING," the 42-year-old wrote on his Instagram story.

"Currently, I'm in a cabin with 4 adults and 7 kids (ages 2-11) which usually is only occupied by maximum of 3 people. There's usually up to 30 people in this particular wagon. We were told we have to fit 135. Walkways are packed. People everywhere. It's sweaty and claustrophobic," he added.

In another Instagram story, Chmerkovskiy shared a heartbreaking exchange he witnessed between a boy and his father.

"What finally broke me is when I was watching an 8-ish year old boy, hysterically crying and not wanting to let go of his father. Verbatim 'if you stay I want to stay too because if they kill you I won't be able to help,'" he wrote. The reality star shares a 5-year-old son with wife Peta Murgatroyd.

Murgatroyd reposted Chmerkovskiy's update on her Instagram story, adding, "@maksimc YOU CAN DO IT!! Get bak home! I am so f****** proud of you for helping those kids on board!"

Earlier on Monday, Chmerkovskiy said he was arrested trying to leave Ukraine. The choreographer was working on the reality competition series World of Dance Ukraine when Russia launched its attack last week. It's unclear what led to his arrest. A rep for the star did not respond to Yahoo Entertainment's request for comment.

"I'm a little nervous, to be honest with you. But I think it's going to be alright. Well, I know it's going to be OK," he said in a video. Chmerkovskiy told fans not to worry if he goes dark on social media. "If I disappear for a little bit, please don't worry. ... I'm going to do my best to keep you updated."

MORE: Maks Chmerkovskiy gets arrested in Ukraine