Mourning the death of a beloved student in a gruesome accident, English teacher Jane Lynch spoke of the 16-year-old in a trembling voice. Friends sent sad Twitter messages expressing their affection for Daniel Fernandez, and hundreds of students gathered Saturday evening for a candlelight vigil at St. Francis Preparatory School in Queens.

The teen was killed after he stuck his head out of the emergency hatch of a double-decker bus and hit the underside of a highway overpass, authorities said. The Friday night accident followed warnings of a security guard on the bus who said he told the teen passengers repeatedly not to open the hatch.

"Sometimes kids don't recognize their own mortality," Lynch said, her voice quivering.

Fernandez was among 65 teens aboard the bus from New York City on its way to a Sweet 16 party in Garfield, N.J., said Steve Coleman, spokesman for the Port Authority of New York and New Jersey. The accident happened as the bus crossed the George Washington Bridge on the way to New Jersey.

The teens were dancing and the bus had gotten hot, the security guard, Alex Franco, told the Daily News.

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

Franco said he had gone downstairs to tell the driver that it was getting too hot.

"Two, five minutes I was downstairs," he said.

But then he heard teenagers screaming, and he saw Fernandez on the floor of the bus. "There was so much blood everywhere," he told The New York Post.

Fernandez, who lived in Queens' Woodside neighborhood, was pronounced dead at a hospital.

Calls to his family home Saturday in Queens rang unanswered.

Friends sent sad Twitter messages reacting to his death.

"Sitting here with your blood on my foot wishing this was all a bad dream. I love you so much dan you were there for me till the last second," wrote one student, who said she was forever scarred.

Students planned to wear blue on the first day of school to honor the teen.

Fernandez was going to be a junior at St. Francis Preparatory. He was a beloved student, said Lynch, who taught him last school year.

"He was an adorable, low-key kid, with a sweet smile," she said. "Kids loved him; he had lots of friends and was popular with the girls."

She said a group of students had a special last project, producing and appearing in a takeoff on the novel "Lord of the Flies," about a group of boys on a desert island who try to govern themselves, with disastrous results.

"He was very hands-on, he took the leadership role," said Elizabeth Gonzalez, a student teacher at St. Francis last year.

Fernandez played the villain in the video students posted on YouTube, she said.

In class, "he was very lively, and high-spirited," she said. "And he had so much potential in his writing."

The school said on its website that it shared in grief and shock over his death. A wake was set for Monday, the site said.

Designer Limousines, which operates the bus, expressed its "deepest heartfelt sympathy" to the teen's family. The company said it would conduct an internal investigation.