“There was no possible way of claiming ignorance,” she wrote in another tweet.
In less than four days, Ms Murphy’s original tweet has been liked by more than 57,000 people and has had more than 30 million views.
“Absolutely disgusting. When I went, people were taking selfies. So disrespectful,” wrote one British journalist.
“I visited in 2005 and every single person in my tour group had cried over the course of the tour,” said a US man.
Australian journalist Georgina Smyth, who works for CBC News in Canada, wrote: “Saw the same thing when I visited. Deeply regretted not confronting people about it.”
“Incredible. So disrespectful. Why are they even there? They should be on a beach,” said another Canadian journalist.
The official account of the Auschwitz-Birkenau Memorial and Museum also responded.
“Pictures can hold immense emotional and documentation value for visitors. Images help us remember,” it said.
“When coming to @AuschwitzMuseum visitors should bear in mind that they enter the authentic site of the former camp where over one million people were murdered. Respect their memory.”
More than 50 million people from all over the world have visited Auschwitz since 1945, according to the website. The official rules of visiting the site in southern Poland include that visitors must “behave with due solemnity and respect”.
