When children kill

The Denver shooting is the latest to shock the United States

The shooting at Columbine High School in Denver is the latest in a string of school attacks that have horrified the United States over the past 18 months.

Both the perpetrators and the victims of these crimes have usually been teenagers.

The spate of violence has forced America to ask difficult questions about what leads a child to pick up a gun and kill another, and what is the appropriate action to take.

On 16 April, a second-year high school pupil fired two shotgun blasts in a school hallway in Notus, Idaho. No-one was injured.

In May 1998, 15-year-old Kipland Kinkel killed two fellow pupils at Thurston Hill High School in Springfield, Oregon - and then murdered his parents.

On the same day, 320km north in Washington state, a 15-year-old boy shot himself in the head after taking his girlfriend off the school bus at gunpoint and to his home in the town of Onalaska.

He shot himself as the girl's father tried to break down the door. The 14-year-old girlfriend was not injured.

Jonesboro killings

The four schoolgirl victims of the Jonesboro shooting

Just two months earlier, two boys opened fire on classmates at Westside Middle School in Jonesboro, Arkansas.

The boys, aged 11 and 13, killed four girls and one teacher, wounding nine more girls and one other teacher.

As the incident fuelled concern about a surge in youth violence, President Clinton instructed the Justice Department to look into the trend of school shootings.

A tide of violence

Other similar incidents:

• 19 May 1998: An 18-year-old at Lincoln County High School shot and killed a student in a school parking lot in Fayetteville, Tennessee, three days before they were to graduate, apparently because they had argued about a girl.

• 25 April 1998: A 14-year-old boy opened fire at an eighth-grade graduation dance at Parker Middle School in Edinboro, Pennsylvania, killing a teacher and wounding two students and another teacher.

• 1 December 1997: A 14-year-old boy shot and killed three girls at Heath High School in West Paducah, Kentucky, while they took part in a prayer circle. Five others were wounded.

• 1 October 1997: A 16-year-old stabbed and killed his mother, before going to school where he shot nine students. His ex-girlfriend and another girl at Pearl High School in Mississippi were killed. Seven other students were wounded and six boys, aged between 16 and 18, were charged with conspiracy to commit murder.

A study by the Department of Education in March found that as many as 10% of US schools suffered serious incidents of violence in the year 1996-1997. In that year alone, schools recorded 11,000 armed assaults and 4,000 rapes or cases of sexual assault.

After the Thurston Hill tragedy, White House spokesman Mike McCurry disputed suggestions that the shootings were only being addressed because they were happening more often in majority white, suburban schools, following years of shootings in which children from minority groups had been killed or injured at inner city schools.

Right to arm vs right to life

The shootings have fuelled the raging debate on gun law in the US.

The right to "keep and bear arms" is enshrined in the second amendment of the US Constitution and is fiercely guarded by the powerful gun lobby group, the National Rifle Association.

But media reports began to identify frightening links between carrying guns and school violence, and called for new legislation on gun control.

Meanwhile, the parents of one of the Jonesboro victims launched a civil lawsuit against the gun manufacturers.

After Jonesboro, the debate raged on in cyberspace, with thousands of people e-mailing their views to BBC News Online's Talking Point. The vast majority of American respondents fiercely defended their rights to carry guns, telling the Brits to 'keep out of their business'.