A series of programmes aimed at stopping radical Islamists from joining the fighting in countries like Iraq and Syria is being launched in the US.
The pilot projects will be run by the Justice Department and will take place in cities across the country, Attorney General Eric Holder said on Monday.
Teachers, mental health professionals and community leaders will be involved, an official told Reuters news agency.
The White House is to host a summit next month on countering extremists.
It is hoped that key members of communities across the country will be able to come together to develop a strategy to stop radicalised young people from joining up.
Police and intelligence officials have long expressed concerns about Westerners who have travelled to Syria and Iraq to join militants who have taken over large areas in both countries in recent months.
Last week, a 19-year-old Colorado woman pleaded guilty to trying to help the Islamic State (IS) group, also known as Isil.
"Today, few threats are more urgent than the threat posed by violent extremism," said Mr Holder in a video message.
"And with the emergence of groups like Isil, and the knowledge that some Americans are attempting to travel to countries like Syria and Iraq to take part in ongoing conflicts, the Justice Department is responding appropriately."
The US State Department recently released a very graphic video entitled Think Again, Turn Away that showed the violence of Islamic State, in an attempt to dissuade would-be fighters.
Tara McKelvey, BBC News, Washington
About 100 US citizens have gone to Syria to battle the government of President Bashar al-Assad, according to Matthew Olsen, director of the US National Counterterrorism Center.
That's a far lower number than in some European countries, like France and the UK.
Some of these Americans, like Douglas McAuthur McCain, have ended up dead.
Besides McCain - who grew up in Minnesota - Nicole Lynn Mansfield and Moner Mohammad Abu-Salha were also killed in Syria.
There are believed to be far more Western fighters coming from some European countries.
UK Prime Minister David Cameron has proposed new powers to seize terrorist suspects' passports.
German authorities recently banned the distribution of propaganda material pertaining to Islamic State and the display of its symbols.