The attack happened at about 22:00 local time (20:00 GMT). A report was made to police in Berlin that a white vehicle had been driven into crowds at a Pride event in the capital.
Hundreds of thousands of people had gathered at Tiergarten park, near the iconic Brandenburg Gate, for the annual event, which is known as Christopher Street Day.
Some people were also stabbed in the incident, with a blade officials believe could have been a machete.
Shortly afterwards, the Pride event was cancelled.
A performance was abruptly brought to a end, with organisers taking to the stage and advising the crowd to start walking towards the exits.
As the message was being given to the crowd, the word “evacuation” was projected onto a large screen on the stage.
Unverified video posted to social media showed large crowds of people leaving the scene as emergency vehicles raced to the scene.
At about 01:00 local time, police confirmed that one woman had been killed and many more had suffered injuries.
A short time later, police confirmed they had found the vehicle believed to have been used in the attack, saying it had crashed into a tree.