STORY: Vadatursky, founder and owner of agriculture company Nibulon, and his wife were killed in their home last week when Russian missiles pounded the southern Ukrainian port city of Mykolaiv.
Speaking to journalists after the funeral ceremony, Vadatursky's son, Andriy Vadaturskyi, said he believed his father's death had not been an accident.
"I don’t want to discuss details yet, but I simply do not believe it was a coincidence," the ex-lawmaker and chairman of Nibulon's supervisory board said.
Several hundred people came to pay tribute, including former Ukrainian President Petro Poroshenko, a close friend of the Vadatursky family.
"I am convinced the missile was guided by the hand of a traitor," Poroshenko told reporters.