Brad Garrett has lashed out at Ellen Degeneres on Twitter.

One current and 10 former employees of 'The Ellen DeGeneres Show' recently came forward to accuse the show's three executive producers - Ed Glavin, Mary Connelly and Andy Lassner - of ''bullying'' and Ellen issued an apology to staff who felt they were not ''treated with respect''.

However, 'Everybody Loves Raymond' star Brad, 60, who appeared on the chat show six times between 2004 and 2007, was not impressed by Ellen's apology.

He tweeted: ''Sorry but it comes from the top @TheEllenShow. Know more than one who were treated horribly by her. Common knowledge.''

Brad tweeted a link to an article detailing Ellen's apology, where she said in a letter to her staff: ''On day one of our show, I told everyone in our first meeting that 'The Ellen DeGeneres Show' would be a place of happiness - no one would ever raise their voice, and everyone would be treated with respect. Obviously, something changed, and I am disappointed to learn that this has not been the case.

''For that, I am sorry. Anyone who knows me knows it's the opposite of what I believe and what I hoped for our show.''

Ellen went on to acknowledge that her show's success - which has seen her win 30 Emmy awards, and 20 People's Choice Awards among many other accolades - wouldn't have been possible without her staff.

She added: ''My name is on the show and everything we do and I take responsibility for that. As we've grown exponentially, I've not been able to stay on top of everything and relied on others to do their jobs as they knew I'd want them done. Clearly some didn't. That will now change and I'm committed to ensuring this does not happen again.''

And the show host has claimed she is working with WarnerMedia on their investigation into the allegations, and will help to determine the next steps to ''correct the issues'' they found.

In the original allegations from the show employees - which were published in a BuzzFeed article - Ellen, 62, was not accused of any wrongdoing, but the employees claimed they were instructed not to talk to her if they saw her in the building.