Two teenagers have been arrested after seeking to copy the Southport killer, it can be disclosed.

Axel Rudakubana was jailed for a minimum 52 years after he murdered three schoolgirls in a knife attack at a Taylor Swift-themed dance class last year.

The first copycat case involved a 17-year-old who talked of emulating Rudakubana and conducted research into obtaining large knives.

Police found a note on his phone headed ‘places to attack’, which included images of a dance school near his home in Cwmbran, South Wales. Location data suggested he had been close to the school just days before his arrest in June.

He also researched other potential targets, including his own school, and told people on Snapchat of a plan to attack the first Oasis reunion concert on July 4 in Cardiff.

He pleaded guilty to possession of a document useful for terrorism, and is to be sentenced in January.

The case was adjourned for psychiatric reports amid concerns he has autism – as did Rudakubana.

In the second case, a boy aged 16 from Merseyside allegedly planned to attack a Taylor Swift-themed event wearing a hoodie in the same way as Rudakubana.

He allegedly visited Southport, collected knives and downloaded the same Al Qaeda manual used by Rudakubana to produce the poison ricin.

He also researched high school shootings and considered an attack on his old school, said prosecutors.

The youth, arrested in August, is also charged with possession of documents useful for terrorism plus of making threats to kill. He is due to enter pleas next month. Neither can be named due to their age.

It comes as referrals to the Prevent de-radicalisation programme with ‘no ideology’ have soared over the past year to make up more than half of all cases, although only 7 per cent were offered intervention.

Rudakubana, turned down three times by Prevent, was 17 when he murdered Bebe King, six, Elsie Dot Stancombe, seven, and Alice da Silva Aguiar, nine, and injured ten others. The first phase of an inquiry into the killings concluded on Friday, after examining missed opportunities to prevent the attack.