The NYPD says it's stepping up foot patrols in the city after three police officers were killed and another three injured in Baton Rouge, Louisiana.

The shooting happened this morning less than a mile from police headquarters.

Officials in Louisiana say one suspect is dead and two others are believed to be on the run.

There's still no word on what led to the shootings.

The White House says President Obama has been briefed on the shooting.

This incident comes in the wake of protests in the city against the death of 37-year-old Alton Sterling.

Sterling was shot and killed by police July 5 after they claimed he had a gun.

Four people were arrested last week in an alleged plot to kill officers in retaliation for Sterling's death.