PHOTO: This undated file still image from video released April 7, 2011, by GlobalPost, shows James Foley of Rochester, N.H., a freelance contributor for GlobalPost, in Benghazi, Libya. In a horrifying 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. (AP Photo/GlobalPost, File)

WASHINGTON (AP) — In a horrifying act of revenge for U.S. airstrikes in northern Iraq, militants with the Islamic State extremist group have beheaded American journalist James Foley — and are threatening to kill another hostage, U.S. officials say. Even so, the U.S. military pressed ahead, conducting nearly a dozen airstrikes in Iraq since Tuesday.

The White House must now balance the risks of adopting an aggressive policy to destroy the Islamic State against resisting any action that could result in the death of another American.

President Barack Obama will also confront the potentially necessary step of pursuing the Islamic State 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 Islamic State militants beheading Foley. Separately, Foley's family confirmed his death in a statement posted on a Facebook page that was created to rally support for his release, saying they "have never been prouder of him."

"He gave his life trying to expose the world to the suffering of the Syrian people," said the statement, which was attributed to Foley's mother, Diane Foley. She implored the militants to spare the lives of other hostages. "Like Jim, they are innocents. They have no control over American government policy in Iraq, Syria or anywhere in the world."

Foley, 40, from Rochester, New Hampshire, went missing in northern Syria in November 2012 while freelancing for Agence France-Presse and the Boston-based media company GlobalPost. The car he was riding in was stopped by four militants in a contested battle zone that both Sunni rebel fighters and government forces were trying to control. He had not been heard from since.

The beheading marks the first time the Islamic State 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-Qaida 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 the Islamic State group'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 gray-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.

Several senior U.S. officials with direct knowledge of the situation said the Islamic State very recently threatened to kill Foley to avenge the crushing airstrikes over the past two weeks against militants advancing on Mount Sinjar, the Mosul dam and the Kurdish capital of Irbil.

Both areas are in northern Iraq, which has become a key front for the Islamic State as its fighters travel to and from Syria.

Senators from Foley's home state of New Hampshire condemned the killing.

"His murder was a cowardly act of terrorism and underscores the threat that ISIL poses to the freedoms we hold dear," said Democratic Sen. Jeanne Shaheen.

Republican Sen. Kelly Ayotte went further, calling for the Islamic State's destruction. "This barbaric and heinous act shocks the conscience and highlights the truly evil nature of the terrorists we confront, who must be defeated," she said.

Other Republican hawks echoed that message, and some questioned Obama's resolve.

"The United States must not cower to these terrorists' ruthless demands by remaining on the sidelines," said Rep. Mike Pompeo, R-Kan., a House Intelligence Committee member and former Army officer.

"ISIL has declared war on the United States, on the American people and on freedom loving people everywhere," added Sen. Marco Rubio, R-Fla., accusing the group of "murdering civilians, raping women and young girls and enslaving them, and carrying out a systematic genocide of anyone who does not share their warped and extremist Islamist views."

Obama, he lamented, has been "unwilling to do what is necessary to confront ISIL."

Since Aug. 8, there have been at least 77 U.S. airstrikes in Iraq on Islamic State targets — including security checkpoints, vehicles and weapons caches. It's not clear how many militants have been killed in the strikes, although it's likely that some were.

Tuesday's airstrikes by American fighter jets and drones centered on targets around the Mosul Dam and were designed to help Iraqi and Kurdish forces create a buffer zone at the key facility, according to a U.S. official. The official was not authorized to discuss the ongoing operations publicly so spoke on condition of anonymity.

The Islamic State militant group is so ruthless in its attacks against all people they consider heretics or infidels that it has been disowned by al-Qaida's leaders. In seeking to impose its harsh interpretation of Islamic law in the lands it is trying to control, the extremists have slain soldiers and civilians alike in horrifying ways — including mounting the decapitated heads of some of its victims on spikes.

The New York-based Committee to Protect Journalists says that more than 80 journalists have been abducted in Syria, and estimates that around 20 are currently missing there. It has not released their nationalities. In its annual report in November, the committee described the widespread seizure of journalists as unprecedented and largely unreported by news organizations in the hope that keeping the kidnappings out of public view may help in the captives' release.

Most of the kidnappings over the past two years have occurred in northern and eastern Syria, where a mix of mainstream rebel factions and jihadi groups hold sway. This year, several foreign journalists were released after lengthy terms in captivity, including three Spanish journalists in March and four French reporters a month later.

Jihadi factions, such as the Islamic State group, are believed responsible for most of the abductions, but government-backed militias, criminal gangs and more moderate rebel factions also have been implicated. The motives range from ransom to prisoner exchanges.

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Associated Press writers Lita Baldor, Bradley Klapper and Julie Pace in Washington, Ryan Lucas in Beirut, Rik Stevens in Rochester, New Hampshire, and Zeina Karam in Beirut contributed to this report.

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