At least 52 persons were killed in a stampede triggered after the police fired teargas shells and warning shots at anti-government protesters during a religious festival in Ethiopia.Thousands of people had gathered for an annual celebration of thanksgiving in Oromiya region when some began chanting and waving a rebel flag. When the police fired teargas shells and guns into the air, crowds fled and caused a stampede, with some people plunging into a deep ditch, Daily Mail reported on Sunday.The crowds chanted "We need freedom" and "We need justice", preventing community elders, deemed close to the government, from delivering their speeches.Some protesters waved the red, green and yellow flag of the Oromo Liberation Front, a rebel group branded as a "terrorist" organisation by the government. According to the witnesses, victims were seen dragged out of the ditch showing no obvious sign of life. Half a dozen people were also taken to a hospital.Ethiopian Prime Minister Hailemariam Desalegn has expressed his "deepest condolences" over the loss of lives that occurred at the celebration, Xinhua news agency reported.The government did not release the official death count yet. The figure came from the opposition Oromo Federalist Congress.