A teacher's aide died Friday afternoon when his car crashed through an entrance at Lincoln High School and burst into flames, police and witnesses said.

Authorities did not immediately identify the victim. The students had been dismissed about an hour before the crash and none were reported injured.

"All the students are safe," Lincoln Police Brian Sullivan said.

It was not immediately clear what caused the crash, which startled bystanders and staff still inside the building.

"I smelled gasoline," said Alexandra Caluori, a teenage witness. "I looked and I saw a car in front of the school — it crashed in front — in flames."

School secretary Carmel Mendoza told reporters that she and another employee tried to pull the man from the burning car after it crashed. She retreated after spotting a pool of gasoline.

Mendoza said the driver was a special education teacher's aide who looked distraught when she saw him leaving the building minutes before.

"There was some serious fire in this incident," Sullivan said.

Firefighters erected tarps Friday afternoon over the hole left by the crash. School officials canceled all extracurricular activities scheduled for the afternoon and over the weekend.