A motorcyclist was killed early Wednesday morning after a single-vehicle crash downtown, the Denver Police Department said.

The crash happened at East Colfax Avenue and North Broadway, between Civic Center Park and the Colorado State Capitol. Police announced the crash just after 4 a.m.

Police said they believe the motorcyclist was riding east on Colfax at a high speed when they lost control and hit a curb. The motorcyclist suffered serious injuries and was pronounced dead at a hospital shortly after, police said.

Police believe speed was a factor in the crash. Other factors such as drug or alcohol use have not been announced.

The investigation into the crash is ongoing, police said. Anyone who witnessed or who has footage of the crash is asked to call Metro Denver Crime Stoppers at 720-913-7867.

The identity of the motorcyclist will be released by the Denver Office of the Medical Examiner after their family has been notified.