By Chris Francescani

(Reuters) - Hundred of teenagers took to social media overnight to mourn a popular New Jersey high school student who was killed on Friday after he stuck his head out of the emergency roof hatch of a double-decker party bus and hit a highway overpass in New Jersey.

"My eyes are still swollen from crying, but I know you're in a better place," wrote classmate Joanna VanWynGarden on a Facebook page created to honor Daniel Fernandez, 16, of Sayreville, New Jersey.

Fernandez was among dozens of students headed to a "sweet 16" party aboard a double-decker bus traveling from New York City to New Jersey around 6:30 p.m, said Steve Coleman, a spokesman for the Port Authority Police Department.

"You didn't deserve any of this. You were such a great kid," wrote Ani Bieber, another classmate. "The last time we spoke two days ago, we were arguing at Katie's sweet 16 and I'd do anything to take it back."

Within 24 hours of Fernandez' death, 931 people had joined a Facebook group honoring his life.

The bus was transporting students from St. Francis Prep in Queens, New York, where Fernandez was beginning his junior year, to a party in Garfield, New Jersey, when Fernandez apparently raised his head through the hatch.

He was pronounced dead after the accident at Hackensack County Medical Center, officials said.

The bus was operated by Designer Limousine, Inc, a Long-Island based charter bus and limousine company that advertises the "largest double-decker party bus in the country."

A spokeswoman said the accident took place on that bus. She referred inquiries to a media specialist, Kyle Kotary, who did not immediately return calls for comment.

A security guard on the bus told the New York Daily News that he warned the festive teenagers to stay away from the rooftop hatch.

"I told them not to open the hatch, like three or four times, but kids, they don't understand," Alex Franco, 41, said.

Franco told the newspaper he then went downstairs to the front of the bus and reported to the driver that it was too hot in the bus.

Moments later, "I heard two guys screaming, ‘Oh my God, oh my God,'' and ran back up to the second floor of the bus and saw Fernandez on the floor.

Coleman referred questions regarding an investigation to the office of Bergen County Prosecutor John Molinelli. No one at Molinelli's office was available on Saturday. The bus company spokeswoman said Designer Limousines had not been contacted by investigators.

(Editing By Tom Brown and Eric Beech)