Shocking documents! Did Hitler kill his niece? A rare discovery after nearly a century: He was in love with her, and they argued shortly before the crime!

A series of archival documents uncovered over the years has raised serious suspicions that Adolf Hitler may have killed his niece, who was found dead in the dictator’s apartment in Munich in 1931, in an incident officially classified as suicide.

Angela “Geli” Raubal, 23, was found dead with a gunshot wound to the chest. The weapon was a pistol belonging to Hitler.

Official documents show that Hitler—who was gaining fame but had not yet seized power in Germany—had left Munich for Nuremberg one day before his niece’s death, a timeline that would establish that he could not have been involved in her death.

But German historian Harold Sandner says he discovered a detail in Munich’s official death register giving the date and time Raubal’s body was found: precisely 10:15 a.m. on September 18, 1931. Two death notices found in the archives also carried that date. If this information is authentic, it would place Raubal’s death around 24 hours earlier than previously believed, indicating that Hitler was in Munich when the young woman’s body was discovered, CNN reports. Official records show that he did not leave for Nuremberg until the afternoon of September 18.

According to historian Sandner, the contradictory records point to a possible cover-up of the killing by police officials who supported Hitler’s Nazi Party. The historian’s findings were first published by the German news magazine Der Spiegel and will be detailed in his forthcoming book, “The Death of Angela ‘Geli’ Raubal: Suicide or Foul Play?”, which is expected to be published next month.

Thomas Weber, an expert on Nazi Germany who has known Sandner for many years, told CNN that the historian is “extremely meticulous” and that his documents are credible.

Many historians believe that Hitler was in love with Raubal and that his behavior toward her had become intensely controlling and possessive. Shortly before her death, Hitler and Raubal are believed to have argued over her desire to leave Munich for Vienna to pursue music studies. The newly uncovered records do not solve the mystery of how Raubal died.

Nevertheless, they reopen questions that have persisted for nearly 100 years about exactly what happened inside his Munich home on the day of her death.