Hundreds of thousands of costumed onlookers watched and cheered as Germany’s beloved Carnival parades made their way through city centres on Shrove Monday, the highlight of festivities each year.

The biggest parade on Shrove Monday, known in Germany as Rose Monday, was held in the western city of Cologne with some 12,500 participants accompanying satirical – and sometimes explicit – floats and throwing some 300 tons of confectionery into the crowds celebrating along the route in bright sunshine.

An investigation into the incident is in full swing, with police yet to determine whether the incident was due to an attack or an accident.

Speaking ahead of Monday’s parade, Cologne police president Johannes Hermanns said he was not worried about security at the event, with a large police contingent deployed to ensure a peaceful celebration.