A British teenager on Monday pleaded guilty to charges of murdering three young girls in a knife attack in northern England in July, a crime that horrified the nation and was followed by days of nationwide rioting.

Axel Rudakubana on Monday admitted committing the deadly attack last July. Officials later said he had been referred to a government counterterrorism program three times before his rampage.

Axel Rudakubana, 18, also pleaded guilty to 10 counts of attempted murder following the attack in summer last year