Donald Kempf Jr., a former senior lawyer in the U.S. Justice Department’s antitrust division, stepped down last year during an internal investigation that would conclude he viewed sexually explicit images on government computers and made false statements when he was questioned about the conduct, according to sources familiar with the probe.

The findings were outlined in a one-page summary of the investigation by the Justice Department’s inspector general, which did not identify Kempf but specified that the official had served as a deputy assistant attorney general.