Average response time by police to a mass shooting is 3 minutes.

It is the worst mass shooting in the nation's history.

It was the beginning of what may be the worst mass shooting in Canada.

Alabama officials said this was the worst mass shooting event in the state's history.

The protagonist is the mother of a boy who has committed a mass shooting at his own high school.

What happened to the other boys accused of mass shootings?"

The descriptions offered no explanation for the worst mass shooting in American history.

All four main Einsatzgruppen took part in mass shootings from the early days of the war.

The girl's family pastor said that she survived the mass shooting by playing dead and remaining still.

The 23 deaths made the attack the deadliest mass shooting in the nation's history.

The international media often reports American mass shootings, making these incidents well known internationally.

Riverton station was the scene of an attempted mass shooting in 1921.

But mass shooting was too public, and too wearing on the killers.

She was accidentally present at a mass shooting in the town square of Konskie.

This attack is listed as a probable motive for the mass shootings.

They soon formed a mutual alliance and plotted a mass shooting.

The killings were an eerie reminder of the nation's worst mass shooting, just over two weeks ago.

The carnage amounted to the worst single mass shooting in Britain's history.

Gun control was hot after another mass shooting.

The sessions are continuing, with police officers responding recently to a mock mass shooting at the school.

The second attack was a mass shooting at a summer youth camp on an island northwest of Oslo.

Wehrmacht soldiers sometimes informed Jews about plans of the mass shootings.

But it is only a portrait, not an explanation for the worst mass shooting in the United States.

She also describes eyewitness accounts of a mass shooting.

There appear to be no survivor accounts of the Jelgava mass shootings.