In his posts, Anthony "Tony" Baker made comments about Jews, women and police at his page @HymanDoodlesack.
The New York Post published many of his offensive tweets, including one written after Israeli Prime Minister Benjamin Netanyahu visited the United Nations. "[The American Israel Public Affairs Committee] makes me want to be a Nazi," he said.
About two months later, he said, "I need the best goddamn-Jew-lawyer money can buy!"
In June he said, "In BKB Park today taking in the Sun (GOD) + signing copies of my new book, Was Columbus a Homo or Was He Just a Jew? NOW in KINDLE #pride."
He has since removed his Twitter page.
"Nothing can excuse anti-Semitic remarks and vulgar insults about women," de Blasio said. "I am disgusted and shocked by these outrageous comments."
In other tweets, Baker attacked City Council Speaker Christine Quinn by saying, "No one wants to touché your vagina, Speaker."
And another tweet, directed at de Blasio, said, "@BilldeBlasio Boy I love that f**king Dude, Bill de Blasio, and I can't wait for him to kick Speaker Quinn's bony ass in '13. #winning."
It was reported by the Post that Baker worked in de Blasio's office since April 2012 and was on a part-time salary of $15,600.