CHARLOTTE, N.C. -- The FBI is now involved in the search for missing 16-year-old, Nathan Kocmond, his father tells NBC Charlotte.

The family was alerted by the police that the FBI has joined the search because they believe the Providence Day student crossed state lines.

Nathan was last seen Monday afternoon, leaving his house around 3:30pm in his 2011 Silver Honda CR-V (License plate: PAH-3753)

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Kocmond is described as a white male, approximately 5-foot-11, with brown hair and blue eyes. He was last seen wearing a green Led Zeppelin t-shirt with black and red Adidas shorts.

His family tells NBC Charlotte that authorities haven't relayed information about having solid leads to Nathan's whereabouts.

They're searching frantically in the Charlotte area and are asking people to continue to spread the word about his disappearance on social media.