The leader of the controversial Church of Scientology routinely physically attacked members of his management team, according to former executives, a Florida newspaper has reported.

Defectors from the controversial organisation who spoke to the St Petersburg Times told the paper that David Miscavige was "constantly denigrating and beating on people". Mike Rinder, the church's spokesman for decades, said he was attacked by Miscavige some 50 times.

"It was random and whimsical," he told the St Petersburg Times. "It could be the look on your face. Or not answering a question quickly. But it always was a punishment."

Rinder and Marty Rathburn were the two highest-ranking executives to leave the church. Rathburn said he saw Rinder "get beat up at least a dozen times just in those last four years … some of them were pretty gruesome".

Church officials denied the allegations and told the St Petersburg Times that Miscavige had never hit a church staffer.

Tom De Vocht, who oversaw the church's spiritual headquarters in Clearwater, Florida, estimated that from 2003 to 2005, he saw Miscavige strike staffers as many as 100 times.

"If it wasn't the answer he wanted to hear, he'd lose it," De Vocht told the paper. "If it was contrary to how he thought, he'd lose it. If he found it to be smart aleck, or it was a better answer than he had, he would lose it."

Amy Scobee, who helped create the group's celebrity network, said she saw many attacks, including an incident when Miscavige choked Rinder until his face turned purple.

Rathburn, Rinder and De Vocht admitted in the St Petersburg Times that they hit others. Rathburn claimed a number of the attacks he carried out were on Miscavige's orders, while De Vocht said he "punched a couple of guys" out of a "survival instinct. If I don't attack I'm going to be attacked," he said.

The defectors also alleged that there was a system of "ecclesiastical justice" that included publicly confessing sins and crimes to a group of peers, and being ordered to jump into a pool fully clothed.

But some of the incidents allegedly seen by the defectors were denied by the people they identified as witnesses. The Church of Scientology said the defectors had all failed within the organisation and were "ethically suspect".

The St Petersburg Times reported that it first asked for an interview with Miscavige on 13 May but was told he was not available for interview before July. When it published the story, part of a three-part series about Scientology, Miscavige wrote to the paper and said he had "uncontrovertible proof that your sources are lying. I am at a loss to comprehend how the St Petersburg Times can publish a story about me and the religion I lead without accepting the offer to speak with me."