A global media watchdog on Wednesday urged authorities to conduct a thorough investigation into the death of a Russian journalist, whose newspaper said he was working on a report claiming Russia planned to sell sophisticated missiles to Syria and Iran. Ivan Safronov, a military affairs writer for Russian daily Kommersant, died Friday after plunging from a stairwell window between the fourth and fifth stories of his apartment building. The Vienna-based International Press Institute is "deeply concerned about Safronov's death and urges the authorities to undertake a thorough investigation of the case," Johann Fritz, the group's director, said in a statement. "Journalists are killed in Russia every year due to their work, and the impunity which accompanies these deaths causes great concern," Fritz added. Kommersant also reported that Safronov, 51, had recently told colleagues he was warned he would face a criminal investigation for possibly releasing state secrets if he reported allegations that Russia had struck a deal to supply Iskander missiles to Syria. The Brussels-based International News Safety Institute released a report Tuesday, saying 88 journalists in Russia have died in the past decade. Russia was second only to Iraq, which had 138 deaths, making them the deadliest countries for the profession, according to the report.