A Ukrainian billionaire, Vadym Yermolaiev, and members of his family are reportedly in critical condition after an apparent bomb attack at an apartment building in Monaco on Monday night.

According to reports, Yermolaiev, also known as Vadim Ermolaev, suffered life-threatening injuries alongside his wife and teenage son after an explosive device detonated at around 10 p.m. on June 29.

Investigators believe the blast was caused by a backpack packed with shrapnel, including nuts and bolts. CCTV footage allegedly captured a suspect leaving bags at the scene shortly before the explosion.

Yermolaiev has been identified by several reports as one of the victims. His wife, Anna, reportedly sustained devastating injuries and is said to have lost both feet in the explosion, while their 13-year-old son was also injured. The family is believed to have been standing near the building's entrance when the device exploded.

The blast severely damaged the entrance to the Cuomo Foundation, a philanthropic organisation based in Monaco.

Authorities say the suspect, described as a man wearing a black hat, tracksuit, white jeans and trainers, fled towards the nearby French town of Beausoleil shortly after the explosion.

Although officials have not formally classified the incident as terrorism, it is being treated as a deliberate attack. Éric Ciotti described the explosion as an attack, expressing support for the victims, emergency responders and security forces.

Monaco's Minister of State, Christophe Mirmand, said preliminary findings suggest the explosive device was packed with bolts and other metal fragments to maximise injuries.

He added that police are collecting evidence and noted that, to his knowledge, such an incident is unprecedented in the history of the Principality.

A manhunt is now underway as authorities continue efforts to identify and apprehend the suspect.