Authorities were trying to identify a man who cursed out and threatened a congressional staffer Wednesday afternoon at Congressman Luis Gutiérrez’s Logan Square office.

About 2 p.m., a man who identified himself as a precinct captain for Ald. Ariel Reboyras (30th) entered the offices at 3240 W. Fullerton and began to yell, curse and insult the staff, Gutiérrez said in a statement.

The incident was caught on two short videos posted to Facebook Wednesday, and show a man threatening and swearing at the staff. At one point he throws an object toward a staffer out of frame.

Ald. Reboyras denied that the man worked for his office.

“I don’t know him,” Reboyras said in an interview. “It’s unbelievable that that occurred. I would never condone that kind of behavior from one of my employees. That’s not my style.”

Reboyras said his office has not been contacted by police or Gutiérrez’s office.

“This is outrageous,” Gutiérrez said in a statement. “To assault federal workers in my office who are serving the constituents of the Fourth District is uncalled for.”

Chicago police said they were notified of the incident and that they were investigating the threats made by the man.

Gutiérrez asked for anyone who knows the man in the video to contact his office or Chicago police.