The Environmental Protection Agency has placed roughly 140 employees on administrative leave days after they signed a public letter expressing concern about the treatment of federal employees and the Trump administration’s regulations on climate and public health.

The letter was organized by Stand Up for Science, a group that planned a March rally in Washington to protest the Trump administration’s steep cuts to federally funded scientific research. Of the 278 E.P.A. employees who signed the letter, 173 signed their names, while 105 signed anonymously for fear of retaliation.