A Staten Island man has been arrested for allegedly threatening the life of New York Knicks owner James Dolan, a police spokesman confirmed.

John Giamella, 19, was arrested on Friday and charged with aggravated harassment for allegedly making threats via his Twitter account against Dolan, the chairman of Madison Square Garden and owner of the New York Rangers.

"James Dolan, it's officially time to die," Giamella allegedly tweeted. That was followed by the tweet, "Death to James Dolan," according to a police spokesman.

Giamella also allegedly posted photos showing himself naked and holding a gun, according to published reports.

The head of security at Madison Square Garden picked up on the threats and alerted police, the spokesman said.