This study examines a hot spot policing intervention where private security guards patrolled a specific area in the city centre of a mid-sized Swedish town during summer weekend evenings and nights, aiming to reduce the number of reported street violence incidents. A follow-up of the intervention, using previous years as a control was conducted to measure changes in the number of street violence rates before and during the intervention. The results show non-significant decreases in the number of reported street violence incidents during the intervention. The results can be interpreted in at least two ways: that the intervention had no effects; or that the small, but non-significant decreases observed, are indeed small effects that can be strengthened by modifying the implementation of the intervention. An additional analysis shows that the changes in crime rates are larger at times when the guards adapted a stricter hot spot policing approach, which indicates that with a more structured implementation of the intervention it might be possible to see larger effects.