BALTIMORE — A school bus drove into oncoming traffic and crashed into a transit bus on Tuesday morning, killing six people and injuring 10 others, police said.

The crash occurred before 7 a.m. Baltimore Police spokesman T.J. Smith said in a press briefing that the school bus struck a Ford Mustang, continued along the road, and struck a pillar on the side of the road. The school bus then entered oncoming traffic and hit the driver’s side of a Maryland Transit Administration (MTA) bus and ripped the driver’s side off of the bus.

The school bus driver was killed, as were five of the 13 total passengers believed to be on the MTA bus, Smith said, though that number could change because police had not yet searched the transit bus at the time of the briefing.

No students were aboard the school bus, which was contracted by Baltimore City Public Schools. Many students take MTA buses to school, but officials could not say how many students ride the No. 10 bus, according to The Baltimore Sun. An aide aboard the school bus, eight MTA bus passengers, and the driver of the Mustang sustained injuries ranging from minor to critical and were taken to the hospital, Smith said.

Smith added that officials could not speculate on the cause of the crash at the time, described the crash scene as “horrific,” and dispelled rumors that the crash was a crime scene. Smith said that he didn’t know if speed was a factor, but noted that a police commissioner observed that there weren't any skid marks, “so something catastrophic took place, and it’s something we’re continuing to investigate."

Police hope to interview the school bus aide about what occurred just before the crash, he added.

Police Commissioner Kevin Davis said in the briefing that the crash scene was “complicated,” and that it was “going to take a lot of resources to get to the bottom of what happened.”

Keith Scroggins, chief operating officer of the city school system, told The Baltimore Sun that the school bus driver worked for school bus contractor AA Affordable Transportation, and was on his way to pick up his first student. The company was involved in a crash in 2012 that injured 13 people, including students, according to the newspaper.

Shown below is a photo of the crash scene from The Baltimore Sun's Twitter page.

Baltimore school bus contractor involved in crash four years ago https://t.co/pnCDmOz9vnpic.twitter.com/ZqBuxOw1NY

— Sun Breaking News (@BaltSunBrk) November 1, 2016