The New York Police Department said it is investigating threats made to CNN anchor Don Lemon via Twitter.

A police spokespersons confirmed Lemon was sent  numerous threatening and anti-black messages to his Twitter inbox from an unknown individual. ” The department took a report for “aggrieved harassment,” and said it has made no arrests. The investigation is ongoing.

A CNN spokesperson could not be reached for immediate comment.

Lemon is one of CNN’s most durable anchors, holding forth for at least two hours each evening  – and sometimes well into the wee hours of the morning when breaking news requires.

The anchor gained some notice recently after reading an open letter on air to  President Donald Trump after he was accused of handling a recent call to a widow of a U.S. soldier recently killed in action.