BUENOS AIRES (Reuters) - U.S. President Barack Obama said on Wednesday the United States can and will defeat Islamic State and rejected the notion put forth by some Republican presidential candidates that Muslims in the United States should be singled out for surveillance.

U.S. President Barack Obama arrives to meet Argentina's President Mauricio Macri (not seen) at the Casa Rosada government house in Buenos Aires, March 23, 2016. REUTERS/David Fernandez/Pool

In his most extensive remarks about Tuesday’s attacks in Brussels in which Islamic State suicide bombers killed at least 31 people and wounded 260 others, Obama said the United States was offering Belgium all assistance to help bring the attackers to justice.

“We will also continue to go after ISIL aggressively until it is removed from Syria and removed from Iraq and is finally destroyed,” added Obama, using an acronym for the group. He was speaking at a news conference with Argentina’s president, Mauricio Macri, while on a visit to Buenos Aires.

Preventing attacks by the Islamist militants, however, is difficult because “it’s challenging to find, identify very small groups of people who are willing to die themselves and can walk into a crowd and detonate a bomb,” he said.

Reacting to the Brussels attacks, Republican presidential front-runner Donald Trump said he would bring back torture and “do a lot more than waterboarding.” Republican candidate Ted Cruz called for heightened police scrutiny of neighborhoods with large Muslim populations, and Trump said it was a good idea.

Obama said one reason there have not been more attacks in the United States is the Muslim American community is successful, patriotic and integrated.

“They do not feel ghettoized,” Obama said. “So any approach that would single them out or target them for discrimination is not only wrong and un-American, but it also would be counterproductive because it would reduce the strength, the antibodies that we have to resist the terrorism.”

Obama, who visited Cuba before traveling to Argentina, noted that Cruz’s father had immigrated to the United States from Cuba, “a country that engages in that kind of neighborhood surveillance.”

“The notion that we would start down that slippery slope makes absolutely no sense,” Obama said.

Obama also rejected a call by Cruz, a senator from Texas, for the United States to carpet-bomb areas held by Islamic State in Syria or Iraq, saying it would be inhumane and would provide Islamic State with an effective tool to recruit more suicide bombers.