Updated

Two British teens have been charged with plotting to bomb a school on the 10th anniversary of the Columbine High School killings in Colorado, prosecutors said Monday.

A 16-year-old and a 17-year-old had a plan to strike on April 20, according to Britain's Crown Prosecution Service. The date marks 10 years since students Eric Harris, 18, and Dylan Klebold, 17, opened fire at Columbine High School in Littleton, Colorado, killing 13 people before committing suicide in the school's library.

The British teens are accused of "conspiracy to cause an explosion likely to endanger life and injure property." The older of the two is also charged with possessing child pornography.

Prosecutors have refused to go into any detail about the charges before their trial. However, a British police official told The Associated Press on Monday that the date was no coincidence. He declined to elaborate, and spoke on condition of anonymity because he did not want to be seen as pre-empting trial proceedings.

Neither the teens nor the location of the school they allegedly planned to bomb can be named under British laws, which bar the identification of minors.

Both were arrested Saturday in Tameside, in the Manchester area. Appearing at Tameside Youth Court Monday, the pair spoke only to confirm their names, dates of birth and addresses during the hearing.

They are due back in court on March 30.