A US national park has posted a series of tweets about climate change that were later deleted.
"Today, the amount of carbon dioxide in the atmosphere is higher than at any time in the last 650,000 years. #climate," said one of the tweets.
The posts by Badlands National Park in South Dakota were widely shared but had all been removed by Tuesday evening.
The National Park Service shut its own Twitter operation briefly on Friday after an apparent clampdown.
The park service had retweeted photos about turnout at President Donald Trump's inauguration.
But the accounts were reactivated the next day after an apology for "mistaken" retweets.
Since then the park service tweets have been about park news and scenery, but on Tuesday afternoon, the South Dakota park started posting tweets about climate science data.
President Trump has previously called climate change a hoax and the White House deleted the climate change policies on its website on the day of the inauguration.
The park service could not be reached for comment.
Meanwhile, a media blackout has been introduced at the Environmental Protection Agency (EPA), according to the Associated Press news agency.
It bans staff from awarding new contracts or posting on any of the agency's social media accounts,
The main EPA account has not posted anything since 19 January, a day before Mr Trump's inauguration.
The new president angered environmentalists on Tuesday with two executive actions that advance two controversial pipelines.
But Mr Trump said the Keystone XL and the Dakota Access pipelines were important because they would create thousands of construction jobs.