Parker Demos and Frederick Hetzel chained themselves to a crane more than 30 m above the ground. The gesture was intended to protest the controversial construction of a training center for law enforcement in the South River Forest.

The police had to scale the building and saw off the activists' restraints to bring them back down using harnesses. The 34 ha complex, at a cost of around 82 million euros, must replace existing facilities deemed unsuitable by the city's mayor. It is expected to be completed in December 2024.