THE editor-in-chief of Poland's leading conservative newspaper, Rzeczpospolita, has left his job after publishing an inaccurate report that explosives were found in the remains of the plane that crashed and killed Polish president Lech Kaczyński and 95 other VIPs in Smolensk, Russia in 2010. This stoked the fire of claims that the accident was an assassination. The reporter of the story and two other employees have also left the paper. The scandal has rocked Poland for a week. Rzeczpospolita's initial front-page story said that investigators recently found TNT and nitroglycerin around the wreck, on 30 seats and on the wings of the Russian-built Tu-154 aircraft. An official report from Russia had blamed the Polish pilot for choosing to land in thick fog, while another from Poland also found fault in Russian ground control. Polish opposition leader Jarosław Kaczyński, the identical twin of the late president, has long suggested that the government is not telling the truth about his brother's death. He also accuses Donald Tusk, the prime minister, of pandering to Russian president Vladimir Putin, who personally oversaw the Russian investigation into the incident—an investigation that was profoundly flawed. Mr Tusk has strongly denied the charges against him, and says they are politically motivated. On the day the Rzeczpospolita story was published, Mr Kaczyński said it was proof that the Smolensk crash was a "murder" of 96 people, and that Mr Tusk no longer had the right to lead the country. But officials then contradicted the newspaper report. "I would like to calm the public. [We] have not found traces of TNT or any other explosive materials," said Ireneusz Szeląg, head of the Military Prosecutor's Office in Warsaw. "Chemical substances of a structure similar to high-energy materials like explosive materials have been found but they could be from many other sources."

Mr Kaczyński reacted by saying this was yet more cover-up. Rzeczpospolita however admitted its story had been inaccurate, and that chemicals found could only possibly be derived from explosives. Mr Kaczyński isn't backing down, and says he has his own sourcing that can corroborate the report.

The Smolensk tragedy had been causing Mr Tusk a lot of trouble. He is seen as responsible for allowing Russia to handle the crash investigation rather than, say, a NATO team on the ground as it was a NATO plane. Mr Tusk was forced to apologise when it was proven that victims' bodies had been mixed up before burial. In January, a prosecutor in the investigation shot himself through the cheek, in what he said was a suicide bid. A couple of weeks ago, a witness in the inquiry named Remigiusz Muś was found dead in his basement in an apparent case of suicide. There has been a call for another witness to be taken into protective custody.

All the while, there is a very dark backdrop to this increasingly bizarre chain of events. The Smolensk crash is especially controversial in Poland because the delegation in the plane were on their way to an official commemoration of the 1940 Katyń Massacre. The second-world-war mass murder of 22,000 Polish officers was undertaken by the Soviet Union, which at the time had good relations with Nazi Germany. Despite the victims being Allied troops, Britain and the United States colluded in the Soviet cover-up of the massacre.

A survey this summer showed around one-third of Poles think it is possible that the Smolensk air crash was an assassination. Most Poles still want an international team of investigators to determine precisely what happened. As long as this does not happen, conspiracy theories will continue to flourish.