The US Justice Department has opened an investigation into whether police officials in Washington have falsified data to make crime rates appear lower than they are, according to two people familiar with the investigation who were not authorised to publicly discuss an open investigation.

The investigation comes amid an escalating – and political – showdown between the Trump administration and the city over control of the police department.

It was not immediately clear which federal laws could have been violated by the possible manipulation of crime data.

But he exaggerated or misstated many facts about public safety in Washington, where crime rates have fallen in recent years.

Mayor Muriel Bowser’s office declined to comment on the investigation. A spokesperson for US Attorney Jeannine Pirro’s office in Washington did not respond to emails seeking comment.