LinkedIn photo of Jofi Joseph, former Director for Nonproliferation at the White House and National Security Council. Photo: Screenshot.

Jofi Joseph, Director for Nonproliferation at the White House and the National Security Council, who was part of U.S. President Barack Obama’s team working on negotiations with Iran, was fired last week. Joseph was revealed on Tuesday as the staffer behind anonymous Twitter handle @natsecwonk that poked fun at colleagues around the White House and Capitol Hill for more than two years, The Daily Beast reported on Wednesday.

The Daily Beast said two administration officials confirmed his identity as the Tweeter and that he was fired.

Joseph previously worked at the State Department and on Capitol Hill for Senators Bob Casey (D-PA) and Joe Biden, the vice-president and former U.S. senator. His wife, Carolyn Leddy, works on the Republican side of the Senate Foreign Relations Committee, The Daily Beast said.