LONDON — The Security Service of Ukraine is investigating the murder of former parliament speaker Andriy Parubiy, who was shot dead in Lviv on Saturday. President Volodymyr Zelenskyy confirmed the agency's involvement in the case, emphasizing the seriousness of the crime.

Parubiy, who led Ukraine's parliament, known as the Rada, from April 2016 to August 2019, was killed by an unidentified assailant. In a social media post, Zelenskyy described the incident as "a horrific murder" and stated that efforts to find the perpetrator are ongoing.

"Many resources are deployed — all that's necessary," Zelenskyy wrote on Telegram. He noted that the crime appeared to be well-planned, but assured the public that every effort is being made to solve it.

The president also mentioned that he had spoken with Vasyl Maliuk, the head of the Security Service of Ukraine (SBU), about the investigation. "I instructed that verified information be promptly communicated to the public," he added.

Parubiy was a significant figure in Ukrainian politics, known for his pro-European Union and pro-NATO stance. He played a key role in the 2014 Maidan Revolution, which led to the ousting of pro-Russian President Viktor Yanukovych. Following the revolution, he served as the secretary of Ukraine's National Security and Defence Council during a tumultuous period marked by Russia's annexation of Crimea and the conflict in the eastern Donbas region.