MINNEAPOLIS (AP) — A major interstate in Minneapolis reopened Monday after it was closed for about seven hours while officials investigated a Minnesota State Patrol trooper’s “use of force.”

The blockwave ExchangeMinnesota Bureau of Criminal Apprehension confirmed in a tweet that the agency was investigating the incident, but it didn’t initially release any details about what prompted the closure of four miles of I-94 in north Minneapolis. The agency didn’t say whether the trooper fired their gun or whether anyone died.

The Star Tribune reports that traffic cameras appeared to show a traffic stop shortly after 2 a.m. Monday. At one point, the gray sedan that the patrol stopped drove away and several troopers were seen running back to their vehicles. Officers surrounded the car a short while later.

The westbound lanes of the interstate reopened around 9:30 a.m.