Jimmy Fallon has apologized to colleagues at NBC’s Tonight Show for allegedly creating a toxic work environment.

“I feel so bad I can’t even tell you,” he told staff on a Zoom conversation, Rolling Stone magazine reported.

It comes after the magazine conducted an investigation into damning charges made by 16 current and former staff members of the US TV show.

They told Rolling Stone that they had felt belittled and bullied for years.

Fallon’s behavior was described as “erratic” depending on whether he was having a “good Jimmy day” or a “bad Jimmy day.”

They claimed to have had “outbursts” of rage.

The visitors’ dressing rooms were referred to as “crying rooms” in the initial Rolling Stone report that disclosed the allegations.

“Writing for late night is a lot of people’s dream jobs, and they’re coming into this and it becomes a nightmare very quickly,” an unidentified source told the magazine.

The journal noted that for individuals who had concerns and communicated them to human resources, the issues remained unanswered.

All current and former employees who spoke to Rolling Stone requested anonymity “for fear of retaliation.”

“We are incredibly proud of The Tonight Show, and providing a respectful working environment is a top priority,” an NBC representative said in a statement. As in any workplace, employees have raised concerns; these have been reviewed, and appropriate action has been taken.”

Fallon reportedly told the show’s staff after the Rolling Stone probe, “It’s embarrassing, and I feel so bad.”

“I apologize if I embarrassed you, your family, or your friends.”

However, some current staffers of the show have rallied to Fallon’s aid.

Fallon was described as “a really, really positive guy” by one source.

“He makes a point of commending you when you do a great job and when he’s happy,” stated the anonymous employee. “I’ve never been belittled or yelled at like that.”

“I’m really happy to work there right now,” claimed another colleague, who had never heard of “crying rooms” before.

Since Fallon took over as host of The Tonight Show in 2014, the show has had nine different showrunners – top-level TV producers.

The show drew nearly 11 million viewers in its premiere with Fallon.

Prior to The Tonight Show, Fallon established himself as the host of NBC’s Late Night With Jimmy Fallon.