Andriy Parubiy, the former head of Ukraine’s parliament, was shot dead by an unidentified attacker in the western city of Lviv on Saturday, officials confirmed.
Ukrainian President Volodymyr Zelenskyy referred on X to the "horrendous murder" of the 54-year-old lawmaker, a prominent political figure who headed the unicameral Verkhovna Rada from 2016 to 2019.
"All necessary forces and means are engaged in the investigation and search for the killer," said Zelenskyy.
Media reported that the lawmaker was hit by several gunshots around noon (0900 GMT) and died on the spot from his injuries.
The reports said a bicycle courier from a delivery service allegedly fired the shots. There was initially no official confirmation of this.
Investigations into the crime and the search for the perpetrator are ongoing, Zelenskyy said.
He said he had been informed about the incident by Interior Minister Ihor Klymenko.
Zelenskyy expressed his condolences to the politician's family.
Born in 1971, Parubiy was the parliamentary speaker from 2016 to 2019. During the pro-Western revolution at Independence Square in Kiev, he also emerged as a commander of a tent camp and leader of the Self-Defence Maidan organization.
In 2014, the year of the pro-Western protests in Ukraine, he held the position of secretary of the National Security and Defence Council of Ukraine.
Kremlin-aligned Russian political scientist Sergei Markov described Parubiy as one of the organizers of "mass murder" in Odessa on May 2, 2014, when several pro-Russian activists died in a fire at the trade union building.
"He was literally a madman," Markov wrote on Telegram. He said Parubiy bore responsibility for the deaths of many people after the Ukrainian leadership in 2014 acted against the Russian-speaking population following the ousting of the former Moscow-friendly president Viktor Yanukovych.
In Odessa, during street battles between Ukrainian nationalists and demonstrators loyal to Moscow in and around the trade union building in the city, several dozen people, mainly government opponents, were killed.
In March, far-right activist Demyan Hanul, who had mocked the victims, was shot dead in Odessa. The European Court of Human Rights (ECHR) in Strasbourg also condemned the Ukrainian authorities in March for the bloody riots and the fire disaster in Odessa.
Last year, ultra-nationalist politician Iryna Farion also died in an assassination in Lviv.
Farion, who had also had trouble with the Ukrainian judiciary due to her anti-Russian statements, was injured by a gunshot to the head in front of her home in July of the previous year.
The 60-year-old, who had also been a parliamentary deputy for the right-wing nationalist Svoboda party in the Verkhovna Rada, died shortly afterwards in hospital, according to the authorities.
The authorities were also investigating a possible Russian connection at the time.
