Eamonn Holmes and Ruth Langsford attend the ITV Gala at London Palladium on November 19, 2015 in London, England.

Ofcom, the U.K.'s media regulator, is looking into a popular morning TV show after its presenter made comments about baseless conspiracy theories which link the coronavirus outbreak to 5G technology.

The watchdog said it received 419 complaints from viewers after TV presenter Eamonn Holmes said the media shouldn't dismiss claims that 5G is spreading Covid-19 — despite the fact that such rumors have been widely debunked by scientists and public health authorities.

"What I don't accept is mainstream media immediately slapping that down as not true when they don't know it's not true," Holmes claimed Monday on the popular ITV breakfast show "This Morning."

"It's very easy to say it's not true because it suits the state narrative. That's all I would say as someone of the inquiring mind."

A spokesperson for Ofcom told CNBC: "We are assessing this programme in full as a priority."

ITV shares were down more than 7% Tuesday afternoon following Ofcom's statement. Holmes sought to clarify his comments, which he said had been "misrepresented."