The owner of a top Bulgarian football club, Lokomotiv Plovdiv, has been shot dead by a suspected sniper at a restaurant in a Black Sea resort town.
Police said 39-year-old businessman Georgi Iliev was hit by a bullet in the chest as he was speaking on the phone.
The killing came after his team won a Uefa Cup game which enabled them to meet England's Bolton Wanderers next.
A police chief quoted by the Associated Press said the attack may be linked to a turf war between criminal gangs.
The agency says Bulgarian Interior Minister Rumen Petkov announced an investigation into organised crime gangs following an emergency meeting with security officials on Friday morning.
Recent years have seen a series of mafia-style killings blamed on gangs seeking control of Bulgaria's drugs and prostitution trade.
Mr Iliev was killed on Thursday evening in Sunny Beach, a resort town near the Black Sea port of Bourgas, police said.
Police chief Krasimir Petrov said some 30 witnesses were being questioned over the shooting, which is thought to be the work of a sniper.
Hours earlier, Mr Iliev's Lokomotiv Plovdiv football team beat Serbian club OFK Belgrade to progress to the second qualification round of Europe's Uefa Cup club championship.
Local media reports said players from the team were due to have joined Mr Iliev at the restaurant to celebrate the result.