Police have arrested the brother of Regina Kruchkov, who is accused of drowning her young son in a bathtub in September, over suspicions that he was linked to the death of his terminally ill mother, Lodmila, after she was found dead in the family's south Tel Aviv apartment on Thursday morning. Vitali Kruchkov, a former IDF combat soldier, was being questioned by Tel Aviv police officers, a police spokeswoman said, adding, "We do not yet know whether a criminal act was involved [in Lodmila's death]." Police were also questioning Yuri, Regina's partner, and Lodmila's caretaker over the death, following suspicions that Lodmila was disconnected from a life support machine in her home. On Thursday morning, police oversaw unsuccessful efforts by Magen David paramedics to resuscitate Lodmila. The 57-year-old woman had been bed-ridden for a long period with a terminal illness, and was hospitalized when her situation deteriorated following the killing of her grandson by her daughter. In September, Regina Kruchkov was accused of drowning her four-year-old son, Michael, telling a Tel Aviv court through her lawyer that she did not know why she did it. The case formed the third shocking incident of a murder of a child by its guardian in a short space of time, and the second drowning of a boy by his mother within one week. Regina had called emergency services and whispered to the operator that she had killed her son before hanging up. The operator traced the call back to a south Tel Aviv address, and dispatched paramedics and police to the home, who discovered the body of four-year-old of Michael allegedly lying on a bed in the apartment. She confessed to killing her son during an interrogation, police said, adding that no motive had been found yet. Kruchkov immigrated to Israel from the former Soviet Union, and lived in a small Tel Aviv apartment by the central bus station with her son, mother, and brother, Vitali, who lived in an adjacent room with a separate entrance. Following the murder of Michael in September, police had also arrested Vitali and Yuri, an act that was condemned at the time by Tel Aviv Magistrate's Court Judge Dan Moor. Moor agreed with the men's lawyers, who said police had no evidence connecting them to Regina's actions. Yuri and Vitali were subsequently released. "What evidence do you have to link him [Vitali] beyond the fact that he lived there?" lawyer Neil Simon demanded of the police representative in court. Simon also blasted the police for failing to translate Vitali's written statement in Russian into Hebrew, and for failing to determine the time of Michael's death.