New York (CNN) -- A 16-year-old boy from New Jersey was arrested after allegedly trespassing at 1 World Trade Center, bypassing security and making his way to the 104th floor of the nation's tallest building, police said Thursday.

Authorities said Justin Casquejo early Sunday allegedly climbed through a 1-foot opening in a fence surrounding the still-under-construction skyscraper, past "do not enter" and "no trespassing" signs and, apparently undetected, got to the scaffolding around the building and started climbing.
According to the criminal complaint, Casquejo told police, "I walked around the construction site and figured out how to access the Freedom Tower rooftop. I found a way up through the scaffolding, climbed onto the sixth floor, and took the elevator up to the 88th floor. I then took the staircase up to 104th floor."

On the 104th floor, Casquejo encountered an "inattentive" security guard -- a contractor from a security company -- and was able to get past him, according to Joe Pentangelo, a spokesman for the Port Authority of New York and New Jersey, which owns the trade center site. The guard has since been fired, he said.

From there, Casquejo told police, he went to the rooftop and climbed a ladder out to the spire of the 1,776-foot building.
Around 6 a.m. Sunday, Port Authority police arrested Casquejo on the property, according to Pentangelo.
New Jersey teen sneaks to top of 1 World Trade Center, police say -

Nice security we got there. Sigh...