The former speaker of the Ukrainian parliament Andriy Parubiy has been shot dead in the western city of Lviv, officials have said.

Unverified footage, purportedly of the shooting, appears to show a gunman dressed as a courier approaching Parubiy on the street and holding up a weapon as he walks behind him, before fleeing. A huge manhunt is now under way for the suspect.

Ukrainian President Volodymyr Zelensky described Saturday?s attack as a ?terrible murder? and offered condolences to Parubiy?s family.

Parubiy, 54, rose to prominence during Ukraine?s Euromaidan mass protests, which advocated closer ties with the EU and brought down pro-Russian former President Viktor Yanukovych in 2014.

A special operation, codenamed Siren, has now been launched by Ukrainian authorities aimed at tracking down and arresting the suspected shooter.

?All necessary forces and means are being deployed,? Zelensky said in a statement.

Ukraine?s prosecutors said ?an unidentified gunman fired several shots at the politician? and that Parubiy ?died on the spot?.

At a news briefing later on Saturday, Lviv police chief Oleksandr Shliakhovskyi said the gunman had ?fired about eight shots from a firearm, which has not yet been identified?.

He added that the attack appeared to have been ?very carefully planned?.

Meanwhile, Lviv?s chief prosecutor Mykola Meret said all possible motives for the shooting were being investigated, including potential Russian involvement.

Sources in Ukraine?s law enforcement agencies told BBC News earlier that seven shell casings were later found at the scene.

The source also said the attacker was dressed to look like a courier for delivery company Glovo. In the video of the incident, the suspect can be seen carrying a yellow delivery bag.

The assailant is also reported to have had an e-bike.

A spokeswoman for Glovo said the firm was ?deeply shocked by the brutal crime? and would co-operate fully with the investigation into the incident.

Parubiy was a pivotal figure in the Euromaidan movement, which began after Yanukovych?s government refused to sign an association agreement with the EU in late 2013.

He organised and co-ordinated Maidan?s ?self-defence? ? armed teams of protesters who guarded the sprawling tent camp in the heart of the capital Kyiv.

He was Injured several times during clashes with Ukraine?s riot police.

After Yanukovych?s ouster, he became secretary of Ukraine?s National Security and Defence Council, during a period when Russia-armed separatists began fighting in eastern Ukraine ? and when Russian President Vladimir Putin annexed the southern Crimea peninsula.

Following Russia?s full-scale invasion of Ukraine in 2022, Parubiy joined Ukraine?s territorial defence.

He had been a lawmaker in Ukraine?s current parliament.

Ukraine?s Foreign Minister Andrii Sybiha described Parubiy as ?a patriot and statesman who made an enormous contribution to the defence of Ukraine?s freedom, independence and sovereignty?.

Sybiha added: ?He was a man who rightfully belongs in the history books.?

Former President Petro Poroshenko said the killing of Parubiy was ?a shot fired at the heart of Ukraine?.

?Andriy was a great man and a true friend. That is why they take revenge, that is what they are afraid of,? he wrote on Telegram, pointing to Parubiy?s contribution to building the Ukrainian army. (BBC)

Update news