The fiery crash happened around 4:15 a.m. Saturday along San Fernando Boulevard near the 5 Freeway.
While the coroner says the victims' bodies won't officially be identified for several days, family and friends are speaking about the people they say were killed.
Relatives told Eyewitness News the victims in the crash were Stephen Stoll, Malak Hariri and Sebastian Forero. Also killed, friends say, were Sameer Nevarez and Sugey Cuevas.
Savannah Underwood, 18, was also in the Nissan but was able to crawl to safety. She was transported to Los Angeles County Medical Center to be treated for non life-threatening injuries.
Burbank police say all six were in a Nissan that was speeding when it lost control, slammed into a concrete pillar and burst into flames.
All of the victims were recent graduates of Burbank High School and John Burroughs High School. Grief counselors will be on hand at both campuses on Monday.
Family and friends have been gathering around a memorial at the site of the crash to pay their respects.
"Sebastian, he was just a great guy. He's the one person I came to pay homage to," said Stasic Markgraf, a friend. "Everybody flocked to him; everyone loved him. He had a great personality, and he was vibrant."
Authorities still have not said if alcohol or drugs were a factor in the crash.
Anyone with additional information about this incident was asked to contact the Burbank Police Department at (818) 238-3100.