The Salt Lake City Police Department is investigating after two separate hit-and-run crashes killed one man and injured two teens.

“I am very concerned about what is happening on our roadways,” said police Chief Mike Brown in a news release, calling the crashes “unacceptable.”

Police started investigating the first crash at 1:43 a.m. on Sunday when SLC911 got information about a person lying on the ground on 700 East near 500 South, the release states. The person, a 31-year-old man, died at the scene.

The preliminary investigation shows that a dark-colored truck going southbound on 700 East hit the man as he used a crosswalk, then didn’t stop, the release says. Detectives are looking for a small, dark Chevy truck with front-end damage.

Police started investigating the second crash at 4:48 a.m. on Sunday when SLC911 got information about two teenagers lying on the ground at 1300 South and West Temple.

Based on the injuries that the 13-year-old and 14-year-old received, it’s likely they were hit by a vehicle and dragged, according to the Salt Lake City Fire Department.

Paramedics transported the teens to a hospital with serious injuries that weren’t life-threatening. The teens were also in a crosswalk when they were struck, and were also hit by a dark truck, but police say they don’t believe the two cases are related.

The crash involving the man on 700 East is the first traffic-related fatality in Salt Lake City this year, the release states.