The trespassing occurred on Saturday afternoon, when the office was closed and the liberal firebrand was in Washington.
The New York City Police Department (NYPD) said the individual was taken to a nearby hospital for psychiatric evaluation. Officials also said the man was emotionally disturbed.
“No one broke into her office. I don’t know where everyone’s getting that," sergeant Brendan Ryan of the NYPD told The Independent, contradicting reports that the individual had breached the actual office space of Ms Ocasio-Cortez.
Mr Ryan confirmed that the incident took place at an address associated with Ms Ocasio-Cortez's political operations, but noted that the building was large and that police stopped the 27-year-old suspect before he could enter any office. The suspect, identified as Douala Hashi, provided officers with an address in Washington, DC, during his booking.
"No burglary, or no breaking and entering into her office or any office," Mr Ryan said He had a dispute with the security guard when he first got there where he grabbed the security guard by the collar and threatened harm getting into the building."
Mr Hashi has been charged with menacing, criminal mischief, and criminal trespassing. Ms Ocasio-Cortez's staff has been made aware of the incident, according to Mr Ryan.
Ms Ocasio-Cortez has become one of the most prominent politicians in Washington since her surprise primary victory last year during the 2018 midterm elections, and represents a surging progressive arm of the Democratic Party.
In the process, the 29-year-old has been on the receiving end of death threats since taking office, leading Capitol Police, for instance, to provide threat assessment training for her staff.