The head of the Turkish state lottery was shot dead in his office by a former lottery employee on Friday, the state-run Anatolian news agency said.
Lottery employees confirmed general manager Ihya Balak had been shot dead around 9:30 am (0730 GMT). They said police had sealed off the building.
Private broadcaster NTV said the attacker, a former inspector at the state lottery, had shot Balak four times and had been detained by the police.
It said the attacker had been the subject of an investigation at the lottery and there were reports of animosity between the two men.
Employees said Balak had shouted for them to call security after the attacker entered his office with a gun and they then heard gunshots, Anatolian said.
The lottery is scheduled for privatization under the country's multi-billion dollar loan agreement with the International Monetary Fund, but no timetable has been fixed.
According to the lottery's Web site it had a turnover of 1.4 billion lira ($1.2 billion) last year.
Balak was born in 1952 and had been appointed general manager in 2003, Anatolian said. He was married and had two children.