Oleksandr Usyk, the undisputed heavyweight world champion, has been released following a brief detention by law enforcement at Krakow airport in Poland, as confirmed by Ukraine's President Volodymyr Zelenskyy.

The reasons for Usyk's detention remain unclear. The champion of the WBC, WBO, and WBA, who also secured a gold medal at the 2012 London Olympics, is regarded as a national hero and has supported Ukraine's war efforts.

Zelenskyy expressed his outrage over the treatment of Usyk, stating on the Telegram messaging app late Tuesday, "I was appalled by this behavior towards our citizen and champion. Our champion has been released, and he is no longer being detained."

Usyk, who plans to attend the heavyweight boxing match between Daniel Dubois and Anthony Joshua in London on Saturday, later clarified that the incident was due to a misunderstanding.

"Friends, everything is alright," Usyk posted on Instagram. "It was a misunderstanding that was resolved quickly. Thank you to everyone who showed concern."

He also expressed his respect for the Polish law enforcement officers, acknowledging their commitment to their duties regardless of stature or titles.

Ukrainian Foreign Minister Andrii Sybiha stated on X that his ministry would reach out to the Polish foreign ministry, deeming the detention "disproportionate and unacceptable concerning our champion."

Heavyweight boxing champion Oleksandr Usyk (right) shakes hands with the Ukrainian Consul General in Krakow, Viacheslav Voinarovskyi, following his release.

Polish TVP Info, a state-run news channel, shared a video on social media showing Usyk being escorted by handcuffed law enforcement officers through the airport.

In May, Usyk triumphed over Tyson Fury to become the undisputed heavyweight boxing world champion in a thrilling match at the Kingdom Arena in Riyadh. At 37 years old, he is the first boxer to simultaneously hold all four major heavyweight titles and the first undisputed champion since Lennox Lewis's reign ended in April 2000.

The Usyk Foundation, established by Usyk, supports the forces in Kyiv amid the conflict initiated by Russia against Ukraine in 2022. The foundation provides various forms of assistance, including the procurement of ambulances and the delivery of humanitarian aid to the front lines.

Yekaterina Usyk, Usyk's wife, shared a blurred image of her husband with uniformed personnel on Instagram, expressing her gratitude that he is safe following a misunderstanding.