Dallas police say officers are responding to a possible active shooter situation at an office building in the north of the city. Police have provided no other details, including whether any shots have been fired or any injuries were reported in 911 calls Monday morning.
Television footage shows a heavy police response, including a SWAT team, at the multi-story office building along an interstate in northern Dallas.
A broken window can be seen on one of the upper floors.
Dallas Fire-Rescue said they dispatched three rescue units to the scene. A Dallas Fire-Rescue spokesman could not confirm whether there have been any fatalities.
People can be seen milling around the office building.