Greek prosecutors launched a preliminary probe on Monday into allegations that a fire investigator was told to "bury" evidence from the country's worst fire tragedy that took more than 100 lives. Criminal negligence charges have already been filed against 20 people in relation to the disaster in Mati, a coastal resort near Athens, on July 23, 2018, which killed 102 people. Over the weekend, the Kathimerini daily reported that fire department investigator Dimitris Liotsios was allegedly told by then fire chief Vassilis Mattheopoulos to "bury" and "doctor" files to "save himself" from retaliation by superiors. The daily said Liotsios had recorded a meeting with the fire chief on his cellphone, and submitted it to judicial authorities. On Monday, the prosecutor's office in Athens filed charges against Mattheopoulos and "anyone else responsible" for "illegal violence", threats and "abuse of authority". Mattheopoulos dismissed the Kathimerini report as "lies", denying any contact with Liotsios. "There was no meeting or contact...he did his job, I did mine," the former fire chief told state TV ERT over the weekend. The minister in charge of police at the start of the investigation, Olga Gerovassili, has also rejected the Kathimerini report as untrue. On Sunday, however, Prime Minister Kyriakos Mitsotakis called the report "chilling". "It is now clear there was an attempted cover-up," the premier said. At the time, the government of former Prime Minister Alexis Tsipras had stressed the difficulty of organising an evacuation with winds blowing at nearly 120 kilometres an hour (75 mph). But in the wake of the disaster, police and fire services gave conflicting accounts of what had gone wrong. The minister responsible for the police Nikos Toskas resigned within weeks, following accusations that police had not secured the area quickly enough nor alerted the fire service to the scale of the fire. Athens prosecutors have already filed criminal negligence charges against 20 people including the regional governor, local mayors and senior officials in the fire service, the port police and civil protection officials. jph/wai/bsp