Six members of a single family were found stabbed to death in a partially burned-out apartment in Rishon Lezion on Saturday morning, in a multiple homicide that has left the country reeling from the scope and brutality of the murders. The family - two grandparents, two parents, and two young grandchildren - had gathered on Friday evening to celebrate the third birthday of a granddaughter. Two red party balloons could be seen hovering against the ceiling of the second-floor apartment on Saturday, over the heads of police officers moving around the home. Police are seeking to understand whether a member of the family committed the murders before taking his or her own life. Alternatively, a person may have entered the apartment and stabbed the family members to death. The dead have been named as Ludmila and Edward Oshrenko, both aged 56, Dimitri and Tatyana Oshrenko, aged 32 and 28, three-year-old Revital Oshrenko, and a three-month old baby, Natanel Oshrenko. Early on Saturday morning, rescue services were called to the address on Nordau Street, after receiving a report of a fire. Firefighters broke down a locked door and forced their way into the home, where they discovered the corpses of six people. Police were called to the scene, and quickly realized that the deceased did not lose their lives in the fire, when stab wounds and puddles of blood were identified on and around every body found in the apartment. Police said the culprit lit the fires in an effort to disguise the stabbings. Officers described encountering bloody bodies lying in beds and other areas in the apartment. "The family had no criminal past or disputes," said Central District Police Cmdr. Nissim Mor, who arrived on the scene. The Central District's Central Unit was called in to lead the investigation, and a media gag order has been placed by police on findings from the murder scene. At the Dagan Deli owned by the family, forensic officers scoured the ground looking for evidence, and questioning neighbors. Back at the murder scene on Nordau street, police set up a mobile crime lab, as forensic officers moved in an out of the apartment.