MILWAUKEE (AP) — Four people, including a 1-year-old girl, were killed in an overnight crash in Milwaukee when a speeding car struck another vehicle in an intersection, police said.

Milwaukee police said a southbound car crashed into a westbound vehicle about 11:45 p.m. Sunday and the force of the impact ejected several people from the westbound car.

A 1-year-old girl, two 15-year-old girls and a 17-year-old boy who were passengers in the westbound vehicle died at the scene, police said. That car’s driver was hospitalized in serious condition, while an injured passenger was listed in stable condition.

Police said a 32-year-old woman who was driving the southbound car was arrested on suspicion of operating a vehicle while intoxicated, although the crash investigation is still ongoing.

At the time of the crash, police said that motorist was traveling at a high speed.

Milwaukee Mayor Cavalier Johnson called that crash and another deadly accident early Monday where a car crashed into a tree, killing the driver and injuring two passengers, “horrifying.”

He noted that his administration has tried to make the city’s roads safer, in part by redesigning streets, but said, “clearly, there is more work to do.”

“Addressing the human factor — the actions of drivers — is a big part of the efforts ahead,” Johnson said.