Matthew Lovett, 18, and two unnamed accomplices aged 14 and 15, were armed with rifles, swords, knives and 2,000 rounds of ammunition when they surrendered to police in Oaklyn, New Jersey -- a suburb less than 10 miles (16 km) from Philadelphia -- after an attempted weekend carjacking, police said.
The trio were allegedly planning to target three middle school students from Oaklyn and then carry out random attacks on as many people as possible.