First woman to lead NYPD resigns after 18 months in the job

Details: In an internal email to staff, Sewell did not mention her reason for stepping away from the largest police department in the U.S.

• "Since I joined you almost a year and a half ago we have faced tremendous tragedy, challenges and triumphs together," she said.
• "While my time here will come to a close, I will never step away from my advocacy and support for the NYPD, and I will always be a champion for the people of New York City," Sewell said.

What they're saying: Adams in a statement thanked Sewell for her leadership over the past 18 months.

• "Her efforts played a leading role in this administration’s tireless work to make New York City safer," Adams said.
• "When we came into office, crime was trending upwards, and thanks to the brave men and women of the NYPD, most of the major crime categories are now down," he added.

• "The commissioner worked nearly 24 hours a day, seven days a week for a year and a half, and we are all grateful for her service. New Yorkers owe her a debt of gratitude."
• Representatives for the New York Police Department referred Axios to the New York City Hall for comment. Representatives for the New York City Hall did not immediately respond to Axios's request for comment.

What we're watching: Sewell's departure date was not immediately disclosed publicly.