STERLING HEIGHTS, Mich. (AP) — Authorities say telephoned threats about a possible mass shooting prompted the cancellation of a hip hop concert in suburban Detroit.

The event headlined by Beast Coast was scheduled for Sunday night at Michigan Lottery Amphitheatre at Freedom Hill County Park in Sterling Heights.

Macomb County Sheriff Anthony Wickersham said someone phoned in threats of a mass shooting at the outdoor concert venue. Investigators are trying to determine who placed the calls.

The threats came just over a week after mass shootings in Dayton, Ohio and El Paso, Texas. Investigators in Texas said a gunman opened fire at a Walmart on Aug. 3, targeting Mexicans and killing 22 people. Less than 24 hours later, another shooter killed nine people in a popular Dayton nightlife area.