A French researcher was denied entry to the United States after US authorities found messages about President Donald Trump on his phone, a French government official said on Thursday.

France’s minister of higher education and research Philippe Baptiste said that the researcher was traveling to a conference near Houston earlier this month when US authorities found that his phone “contained exchanges with colleagues and friends in which he expressed a personal opinion on the Trump administration’s research policies.”

The researcher was then denied entry to the US and expelled from the country, Baptiste said.

The French ministry of higher education and research said that he worked in the field of space research, and that the incident took place on March 9.

“Freedom of opinion, free research, and academic freedom are values that we will continue to proudly uphold,” Baptiste said in a statement.

“I will defend the right of all French researchers to adhere to these values, while respecting the law, regardless of the country in which they find themselves,” he added.

“If an individual has material discovered on their electronic media that raises flags during an inspection, it can result in further analysis. Claims that such decisions are politically motivated are completely unfounded,” Hilton Beckham, CBP Assistant Commissioner of Public Affairs, said in a statement.

This is a developing story and will be updated.

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