The BBC’s director general has told MPs he made the decision to pull a documentary off iPlayer about children’s lives in Gaza because he “lost trust” in it.

The BBC has already apologised over “serious flaws” in the making of Gaza: How to Survive a War Zone, after it emerged its 13-year-old narrator was the son of a Hamas official.

Tim Davie said he removed the film while they investigated after concerns had been raised about the boy’s connection to Hamas, a proscribed terrorist group in the UK and others.

The independent company behind the film has said it asked if the boy had any connection to Hamas, which was not disclosed. The BBC said it then also failed to uncover the fact.

Davie said on Tuesday the BBC had received about 500 complaints that the film was biased against Israel and another 1,800 over its removal from iPlayer.

Hoyo Films, the independent company that made the documentary for the BBC, has said it is “cooperating fully” with the BBC to “help understand where mistakes have been made”.

The initial internal review by the BBC found Hoyo had also paid a member of the boy’s family “a limited sum of money for the narration”.

Concerns were raised when it aired last month because it centred on a boy called Abdullah – the son of Hamas’s deputy minister of agriculture.

“There were specific concerns – specific questions – about the father of the boy. And as we dug into it, we found out we were not told,” Davie told the Culture, Media and Sport committee on Tuesday.

“There is a lot of frustration and disappointment. We’re very sorry to the audience,” he said.

“If you’re asked a number of times [about the boy’s family] and that question was not answered… that is basics.

“And at the need of the day, as editor in chief, I have to be secure, and at that point, quite quickly, I lost trust in that film and therefore I took decision to take it off iPlayer while we do this deep dive.”

He said the BBC had launched a “forensic analysis” into what had happened. Davie did not not rule out putting the documentary back onto iPlayer once this had taken place.

He explained that it was a “very difficult decision” and a “very hard situation” for the BBC to find itself in.

“There was absolutely legitimate journalism to be done and the voices of those children in Gaza is absolutely something we need to hear – that’s what makes it frankly frustrating where we are.”

He said the broadcaster had a “rich and important current affairs history” in the Middle East and the documentary maker had a “great reputation”.

Hundreds of media figures signed a letter last week criticising its removal from the BBC’s streaming platform.