Australian police said on Saturday they had thwarted an imminent terror attack after discovering explosives at a Melbourne home and arresting a 17-year-old boy, in the latest example of the threat posed by radicalized teenagers in the country.Acting on a tip-off from the national security phone line, police and security agencies began investigating the youth and later raided his home in Greenvale, 20 kms (12 miles) north of Melbourne, on Friday when the threat was "imminent."The bomb squad moved three improvised explosive devices to a nearby park where they were "rendered safe" and said there was no longer a threat to the community, police told a news conference.The teen, who cannot be identified due to his age, was charged with terrorism-related offenses and remanded in custody to appear before the Children's Court in a closed sitting on Monday, police said.The boy's family were described by police as "caring" and "very, very distraught" over the arrest."These are extremely serious offenses and they did involve the use of improvised explosive devices," federal police deputy commissioner Mike Phelan told reporters."Had we not intervened, there was a real threat of action being taken."Police said an investigation was under way and declined to say whether the incident had any links to Islamic extremism.They did confirm, however, that there was no link to last month's terror raids in Melbourne and the subsequent arrest of five teenagers over the planning of an Islamic State-inspired terrorist attack against police officers on the national ANZAC day holiday.Local media reported that the teen had become more active on Facebook in recent weeks, commenting on the war in Syria and that the attack was to take place during the Mother's Day Classic fun run on Sunday, which attracts tens of thousands of participants in cities around Australia."It is deeply troubling to police that such young people in our community are becoming disaffected in the way in which they are and considering endangering the lives of many Australians," Phelan said.Australia, a staunch ally of the United States and its action against the Islamic State group in Syria and Iraq, raised the national terror threat level to "high" for the first time last September."We know that we face a very serious terror threat," Prime Minister Tony Abbott told reporters in Darwin on Saturday."It's important that we don't underestimate the terror threat but it's also important that we keep it in perspective."