CHICAGO — A man walks up to a squad car and opens fire on two sheriff’s deputies sitting inside. Two police officers are shot after responding to sounds of gunfire during a protest.

The shootings — one in Los Angeles and the other 2000 miles (3,200 kilometers) away in Louisville, Kentucky, less than two weeks later — are stark reminders of the dangers law enforcement officers face at a time when anger toward them in the wake of police killings of Black Americans, such as George Floyd and Breonna Taylor, has boiled over.