One of Ukraine’s richest men was injured after a bomb detonated in the lobby of a residential building in Monaco.

Vadim Ermolaev, who is sanctioned by Kyiv, sustained life-threatening injuries from the explosion at around 9pm on Monday.

His partner is believed to have lost both feet in the blast.

The attacker was seen fleeing on foot to Beausoleil, France, after detonating a suspected parcel bomb inside the lobby of the property on Rue du Révérend Père Louis Frolla, according to Monaco’s prosecutor-general.

Police said the device contained bolts and buckshot. A manhunt to locate the suspect is ongoing.

Mr Ermolaev, a property magnate, was sanctioned in 2023 for selling alcohol in Russian-occupied Crimea.

A 13-year-old “very likely related” to the couple suffered less severe injuries, and the three victims were taken to hospital in Nice.

The bombing has shocked the principality, a haven for the wealthy which boasts one of the lowest crime rates in the world.

“It was likely a terrorist attack,” Christophe Mirmand, Monaco’s minister of state, said. “This is the first time in history, to my knowledge, that such an act has taken place in the principality.”

Monaco’s authorities subsequently ruled out the possibility of a terror attack, sources told French media.

Prince Albert II described the attack as a “heinous crime” and “a shock to the entire Monegasque community”.

Monaco’s government said the surrounding area had been cordoned off and the six other unoccupied flats inside the building had been secured.

Silvano Ippolito, a nearby resident, told France’s BFM television that he had suspected the explosion was a gas leak at first.

Then he saw “a woman slumped over and covered in blood” on the building’s stairs, along with “a little boy who was bleeding on the ground with a person who was trying to help him”.

“She was missing her feet,” Mr Ippolito added.

Mr Ermolaev suffered burns and was hit by shrapnel and his partner has undergone an amputation, sources told local media.

A young man was also taken to hospital in Nice after sustaining burns and bruises, reportedly having a bolt from the bomb lodged in his leg.

A further two people, including a domestic worker and caretaker who witnessed the woman’s injuries, were taken into emergency care to be treated for shock.

Footage on social media showed several firefighters carrying a person out of the property on a stretcher, with their condition unclear.

Mr Ermolaev, who obtained Cypriot nationality in 2019 and renounced his Ukrainian citizenship, relocated to Monaco just after Russia’s full-scale invasion of Ukraine in 2022, a source close to the investigation told Le Figaro.

The oligarch, 58, built his wealth in real estate. In 2001, he founded Alef Estate, which specialises in office, retail and residential buildings in Dnipro, a city that has come under heavy fire since the war began.

However, he has fallen foul of Ukraine’s government in recent years.

According to Kyiv’s national security and defence council, which operates a register of sanctioned individuals, the penalties on Mr Ermolaev include asset freezes and trading restrictions within the country.

Mr Mirmand said intelligence services were investigating the victims’ background and would “determine if others might be facing specific threats”.

In a statement from Monaco’s royal palace, Prince Albert said: “We trust in [the authorities] to quickly bring to light the circumstances of this tragedy, identify those responsible and provide all of the answers, at every level.

“More than ever, the principality of Monaco will remain united and determined in the face of violence and crime. The security of our community has always been a priority; it will remain that way more than ever, regardless of the threats.”

Eric Ciotti, the Right-wing mayor of Nice, wrote ⁠on X: “The attack committed this evening is a ⁠tragedy for Monaco.”