James Foley’s parents broke down several times Wednesday as they remembered their slain son, who they praised as a dedicated journalist who was also a humanitarian.

Foley, a 40-year-old American journalist, was kidnapped in November 2012 while freelancing for Agence France-Presse and the Boston-based media company GlobalPost. He was held in captivity until he was executed by Islamic State (ISIS) militants this week. The group released a video purporting to show Foley’s killing, and said other American journalists would also die if the U.S. did not cease its airstrikes in Iraq.

Speaking to a group of reporters outside their New Hampshire home, Foley’s parents, Diane and John, called him a “great American” and focused on their son’s virtues instead of his death.

In this November 2012, file photo, posted on the website freejamesfoley.org, American journalist James Foley is shown covering the civil war in Aleppo, Syria. In an act of revenge for U.S. airstrikes in northern Iraq, militants with the Islamic State extremist group have beheaded Foley and are threatening to kill another hostage, U.S. officials say. (Nicole Tung/Associated Press) “He was as much a humanitarian as a journalist,” his father said, recounting a story of Foley holding a fundraiser to get an ambulance for the war-torn Syrian city of Aleppo.

Diane Foley said she had hoped her son wouldn’t go back to Syria in 2012, but he was committed to the story.

“He just felt that the world had to know … the world had to know about the evil,” she said.

“He felt this was his passion. His reason in life,” John Foley said.

Obama condemns ISIS

U.S. President Barack Obama called and spoke with the parents on Wednesday, the same day he held a news conference in which he vowed a “relentless” effort to stop ISIS.

A group like (ISIS) has no place in the 21st century. - U.S. President Barack Obama

"Jim was taken from us in an act of violence that shocked the world," Obama said. "No just God would stand for what they did yesterday and what they do every single day."

Obama spoke in televised remarks from Martha's Vineyard in Massachusetts, where he's vacationing with his family, a day after the militants released a video showing the U.S. journalist being beheaded.

President Barack Obama pauses as he speaks about the killing of journalist James Foley during a statement in Edgartown, Mass., Wednesday. (Jacquelyn Martin/Associated Press) The president said the group's victims are overwhelmingly Muslim, and no faith could justify its actions. "A group like [ISIS] has no place in the 21st century."

The U.S. military pressed ahead with its campaign, conducting nearly a dozen airstrikes in Iraq since Tuesday. The White House must now balance the risks of adopting an aggressive policy to destroy ISIS against resisting any action that could result in the death of another American.

Obama will also confront the potentially necessary step of pursuing ISIS in Syria, where the U.S. has resisted launching airstrikes or deploying significant American firepower. The president was scheduled to make a midday statement Wednesday about Foley's killing.

U.S. officials confirmed a grisly video released Tuesday showing ISIS militants beheading Foley.

Prime Minister Stephen Harper also addressed Foley’s killing, calling it part of ISIS’s campaign of “really shocking and degrading and disgusting terror” in Iraq and Syria.

Harper said the rapid growth of ISIS represents a long-term threat to the security of countries in the region, and also Canada.

“It’s that serious,” Harper said, adding Canada may announce new steps to deal with ISIS in the coming days.

GlobalPost details final email

GlobalPost’s President and CEO Philip Balboni told reporters Wednesday in Boston that Foley's kidnappers threatened to kill him in response to U.S. bombings in Iraq last week.

Balboni said a threatening email sent to Foley's family was "full of rage" but made no demands. He says the kidnappers ignored pleas for mercy.

GlobalPost President and CEO Philip Balboni said his company left 'no stone unturned' in its attempts to free Foley. (Elise Amendola/Associated Press) ​Balboni says the company spent millions on efforts to bring Foley home including hiring an international security firm.

"We left no stone unturned," Balboni said.

When asked if Foley’s death would deter other journalists, or GlobalPost, from covering Iraq and Syria in the future, Balboni struck a defiant tone.

"To pull back now would be to give these evil people a victory," he said.

"We’re sure as hell not going to stop."

Balboni also praised Foley, who came to journalism after a career in teaching, as a journalist, calling him "a wonderful person" who loved his job and his colleagues.

1st time ISIS killed U.S. citizen

Journalist James Foley, of Rochester, N.H., is shown in a May 2011 file photo. Foley is being remembered as a dedicated and passionate journalist. (Steven Senne/Associated Press) The beheading marks the first time ISIS has killed an American citizen since the Syrian conflict broke out in March 2011, upping the stakes in an increasingly chaotic and multilayered war. The killing is likely to complicate U.S. involvement in Iraq and the Obama administration's efforts to contain the group as it expands in both Iraq and Syria.

The group is the heir apparent of the militancy known as al-Qaeda in Iraq, which beheaded many of its victims, including American businessman Nicholas Berg in 2004.

The video released on websites Tuesday appears to show the increasing sophistication of ISIS's media unit and begins with scenes of Obama explaining his decision to order airstrikes.

It then cuts to a balding man in an orange jumpsuit kneeling in the desert, next to a black-clad militant with a knife to his throat. Foley's name appears in both English and Arabic graphics on screen. After the captive speaks, the masked man is shown apparently beginning to cut at his neck; the video fades to black before the beheading is completed. The next shot appears to show the captive lying dead. The video appears to have been shot in an arid area; there is no vegetation to be seen and the horizon is in the distance where the sand meets the grey-blue sky.

At the end of the video, a militant shows a second man, who was identified as another American journalist, Steven Sotloff, and warns that he could be the next captive killed. Sotloff was kidnapped near the Syrian-Turkish border in August 2013; he had freelanced for Time, the National Interest and MediaLine.

British Foreign Secretary Philip Hammond said the militant fighter shown in the film appears to be British. It was fresh evidence of the insurgents' increasingly sophisticated use of Western fighters to mobilize recruits and terrorize enemies.

The National Security Council issued a statement Wednesday confirming that the video was authentic, as Twitter and some other social media outlets tried to block its spread. Twitter CEO Dick Costolo tweeted that his company was "actively suspending accounts as we discover them related to this graphic imagery." He gave a link to a story about Foley's killing.