A makeshift bomb which detonated outside a residential building in Monaco has injured three people, with reports suggesting a Ukrainian tycoon is among them.
Police have launched a manhunt to find the suspect, but it is believed he may have fled across the border to France.
Surveillance footage appeared to show him travelling on foot into the neighbouring French town of Beausoleil.
The suspect acted alone and remains at large, Monaco's chief prosecutor said.
Police have opened an attempted murder investigation but are not qualifying it as a terrorism investigation, prosecutor Stephane Thibault said.
One of the three injured people is a woman in life-threatening condition, he said.
The other two are a man who is no longer in a life-threatening condition and a child whose life is not in danger, he added.
Local media reports suggest that a Ukrainian construction magnate and his family were among those hurt.
He has been named as Vadym Iermolaiev, with Ukrainian media claiming he has previously been targeted with sanctions because of his ties to Russia.
The injured woman is being treated at a hospital in Nice, Christophe Mirmand, the minister of state for Monaco, told French news broadcaster LCI.
Her partner and a 13-year-old child suffered less severe injuries but remain in hospital, he added.
The three were "apparently returning home peacefully" in the early evening according to surveillance footage, Mr Mirmand said.
"They were caught in the explosion as they crossed the threshold of their apartment building," he added.
"It appears that the family was specifically targeted," he said.
He also noted that the alleged perpetrator "had walked around the area several times while waiting for the victims," according to surveillance footage.
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Monaco's leader Prince Albert II described the explosion as an "odious act".
Detectives across both countries are now investigating, but the attacker's motive is unclear at this stage.
CCTV footage from the moments before the attack appeared to show a man leaving a backpack at the building's entrance shortly before the blast.
Eric Ciotti, the right-wing mayor of nearby Nice, described the explosion as "a tragedy for Monaco".
It happened in the centre of the tax-free microstate on the French Riviera, which is known as a haven for billionaires and their luxury yachts.
(c) Sky News 2026: Monaco: Three injured including Ukrainian tycoon as makeshift bomb explodes outside re
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