At least two people have died, after six people were shot, in the US state of Maryland.
A 16-year-old boy has been shot and wounded, and a 14-year-old arrested, following an argument outside a school, in the US state of Utah.
At least seven people have been killed, after a four bus collided with a lorry, in the US state of California.
At least two American advisers, one soldier and one civilian, have been killed, and three others wounded, following an attack by a lone gunman, at a military base, in Afghanistan.
Two US soldiers have reportedly been wounded, after a roadside explosive was detonated during a regular patrol, in eastern Afghanistan.
At least one person has died, and more than 100 others have been injured, following a train derailment and crash, at a station, in the US state of New Jersey.
At least three people, reportedly two school children and a teacher, have been shot in a rural elementary school, in the US state of South Carolina.
At least 21 people, including three civilians, have been killed, following a suspected US airstrike against Islamic State militants, in Afghanistan.
At least one firefighter has been killed, following an explosion at a drug lab, in the Bronx region of New York.
At least nine people have been injured, following a shooting, outside a shopping centre, in Houston, in the US state of Texas.