CNN host Anderson Cooper has hit out at Donald Trump Jr after the president’s son promoted an image purporting to show him giving a false impression of the damage caused by Hurricane Florence.

On Twitter, Mr Trump shared an image of Mr Cooper standing in waist-deep flood water while a technician stood in much shallower water by a broadcast camera.

He added the message: “It’s a shame that CNN’s ratings are down 41%. What’s worse is there’s a simple solution that they refuse to accept. Stop Lying to try to make @realDonaldTrump look bad.”

But the photograph was in fact taken in 2008 after Hurricane Ike devastated parts of Texas and the Caribbean in September that year, Mr Cooper said in a nearly nine-minute segment on Monday night.

The 51-year-old journalist said he had been reporting near Bridge City, Texas, following the storm and was standing in deep water in a culvert beside a highway in order to demonstrate Ike’s “extensive flooding”.

People were still waiting to be rescued from their homes at the time of the report, Mr Cooper said, and emergency vehicles were using the highway for that purpose.

The water behind him was deeper still, he said, and provided clips from his original broadcast to show he had also reported that its levels were receding. Claims online that he was kneeling in the water to make it appear deeper were “frankly idiotic”, he said.

His crew were standing at the side of the road in order not to damage their cameras, he added. “You can’t put camera equipment in deep water,” Mr Cooper said. “You have to keep the cameras dry.”

He continued: “You could argue I didn’t need to be standing in waist-deep water. I could have stood on the road with the camera crew, but ... I didn’t want to be roaming around on the highway, interfering with rescue vehicles in any way.

“I also wanted to show people how deep the water was, and how dangerous it is for anyone driving [if they came off the road].”

Donald Trump and his supporters have frequently accused journalists of peddling “fake news” when they object to coverage of the president. CNN has been a favourite target.

The image of Mr Cooper was shared widely online including on the r/TheDonald subreddit and by Gavin Smith, a former Trump campaign worker, who tweeted the image a day earlier than Mr Trump. He posted: “Absolutely disgraceful! Apparently #HurricaneFlorence wasn’t devastating enough for @CNN’s @andersoncooper – so he had to exaggerate for his live shot. #FakeNews at its finest!”

In his rebuttal video, Mr Cooper also mocked Mr Trump, calling him “Donnie Junior” and adding: “I know he considers himself an outdoorsman and pays a lot of money to be led to wildlife in Africa that he then kills, but I’m not sure that he’s actually ever been to a hurricane or flood.

“I didn’t see him down in North Carolina the last few days helping out, lending a hand, but I’m sure he was busy doing something important besides just tweeting lies.”

Mr Trump did not initially respond directly on Twitter to the video, but retweeted Andrew Surabian, another former Trump campaign worker, who had said: “The only garbage I see is @AC360 outright lying about Don Jr. supposedly saying the viral pic was from Florence. He literally did no such thing. The ‘evidence’ CNN provided on screen doesn’t even reference Florence. You guys can’t even fact check without spreading #FakeNews.”

While Mr Trump’s tweet did not contain the word “Florence”, its timing and subject matter – following not only Hurricane Florence but also a federal report critical of the US government’s response to Hurricane Maria in Puerto Rico, which President Trump has railed against – appeared to make the reference clear.

Mr Trump took the same line later on, tweeting: “Not surprised @AC360 lied about me on @CNN last night. Par for the course. I never said the pic of him was from Florence. When I tweeted out the picture of @AC360 it was with a link to an article about CNN’s dwindling ratings. Nothing to do with Florence.”

The picture accompanying the Breitbart article Mr Trump linked to was of another host, Don Lemon.

Storm Florence’s rising floodwaters continued to threaten communities across the Carolinas on Tuesday after killing dozens of people, as the northeastern US prepared for potential heavy rains and tornadoes.

Widespread flooding has lapped at the roofs of houses, turned highways into rivers and left thousands requiring rescue. Waterways continued to rise on Tuesday, according to the National Weather Service (NWS).

“Flooding is still going to be a concern into the weekend and into next week,” said Hal Austin, an NWS meteorologist, noting there was a chance of rain for the region on Tuesday and Wednesday. Hoping for dry conditions, he added: “No more water, not even a drop, please.”

At least 32 people have been killed by Florence, including 25 in North Carolina and six in South Carolina. One person was killed when at least 16 tornadoes spun out of Florence in Virginia on Monday, where dozens of building were destroyed, the NWS said.