A teenager arrested over an alleged plan to carry out a school massacre in South Australia's Riverland region has been charged with solicit to murder.
The 18-year-old man, who is already facing four aggravated counts of threatening to kill, was re-arrested on Friday morning and charged with the additional offence.
He made no application for bail during a brief appearance in the Adelaide Magistrates Court and was remanded in custody.
Another teenage boy, aged 16, is also charged with solicit to murder over the alleged plan to attack the school with guns and explosives before the end of term.
Police allege the attack was intended to result in significant loss of life and casualties but they say there is no evidence the teens actually had any guns.
It is alleged police found the 16-year-old with knives, homemade body armour and materials that could be used to make bombs during a search of his home last month.
They say the duo had told others about their plans which is how the information was brought to the attention of police.
The offence of solicit to murder carries a maximum penalty of life imprisonment.
The 18-year-old will face court again in January, while the 16-year-old will appear in the Adelaide Youth Court on December 5.
