Ukraine’s Prosecutor General Ruslan Kravchenko published dramatic surveillance footage on Friday, July 17, showing the moment a bomb exploded outside a Monaco apartment building on June 29, seriously injuring Ukrainian-born businessman Vadym Yermolaiev, his partner and their 13-year-old son.

According to Kravchenko, the footage was recovered by the Security Service of Ukraine (SSU) from a surveillance camera that those behind the attack had secretly installed near the scene in order to confirm the bombing had been carried out. The recording had reportedly been deleted by the perpetrators, but SSU specialists were able to restore it. Kravchenko described the recovery as a key piece of evidence the suspects had attempted to destroy, and thanked SSU operational staff, National Police, investigators and prosecutors for their coordinated work on the case.

Watch the footage here.

The video shows a person placing a bag at the entrance to the building before walking away. Minutes later, Yermolaiev, his partner and their teenage son approach the entrance, at which point the device detonates. Investigators say the explosive was remotely triggered.

The footage’s release comes amid a fast-moving investigation that has already produced several major developments. Anastasiia Berezovska, the 39-year-old Ukrainian national identified by Interpol as the main suspect in the bombing, was found dead near Kyiv on July 7. Ukrainian authorities have since detained two men, Vladyslav Reut, a serving officer with Ukraine’s Defence Intelligence agency (DIU), and Vitalii Zhykovych, a former officer with Ukraine’s Security Service (SBU), on suspicion of her murder. Both were ordered held in custody without bail by Kyiv’s Pechersk District Court on July 9, and both have denied guilt in her killing.