NYC mayor "shocked and troubled" by teen's climb to top of WTC spire

Matthew says: "The new World Trade Center has been hailed as one of the world's most secure sites. A 16-year-old slipped through a fence, eluded a security guard, and spent two hours early Sunday morning atop the unfinished 1,776-foot tower at the top of 1 World Trade Center."

Justin Casquejo, a 16-year-old described by a friend as an adventure-seeker who loves to climb precarious places, spent about two hours early Sunday atop the symbolic and unfinished 1,776-foot tower, authorities said. He's not accused of doing any damage, but the alleged escapade stirred what-ifs about the notion of someone being able to infiltrate the nation's tallest skyscraper.

"Obviously, it was shocking and troubling," said Mayor Bill de Blasio, "and I don't know how possibly it could have happened."

NJ teen bypasses guard, reaches WTC spire