The Dallas Police Department reports there have been several cases of cars being struck by large rocks and cement chunks on Interstate 35 near the Louisiana Avenue overpass.

At least four people have called 911 in the past week to report someone throwing rocks off the overpass. The latest incident happened around midnight Friday when the vehicle Yolanda Muñoz was driving with her daughter as a passenger was hit. They initially thought someone had shot at their car, Fox 4 reports.

Police say they don’t yet have a description of the suspects.