WASHINGTON (AP) — John Durham, the federal prosecutor tapped to investigate the origins of the Russia investigation, has been presenting evidence before a grand jury as part of his probe.

That's according to a person familiar with the matter who spoke to The Associated Press on Friday.

The development is a potential sign that Durham may be mulling additional criminal charges beyond the one he brought last year against a former FBI lawyer who admitted altering a document related to a Trump campaign aide who’d been under FBI surveillance.

The The Wall Street Journal reported earlier Friday that Durham was presenting evidence to a grand jury and contemplating charges against some FBI employees and others outside government.