The United States and several allies launched airstrikes inside Syria for the first time late Monday, the Pentagon said, a heavy bombardment against multiple targets that marked an aggressive expansion of President Obama's war on Islamic State militants.
Waves of U.S. fighter jets, bombers and armed drones slipped behind Syria's fortified air defenses to drop precision-guided bombs on militant positions, while Navy ships offshore fired lethal salvos of Tomahawk cruise missiles.
Targets included fuel and weapons depots, command and control facilities, training camps and other targets in the Sunni extremists' stronghold in Raqqah, in northeastern Syria, and along the border with Iraq.
Some residents near Raqqah took to Twitter more than half an hour before the Pentagon announced the bombing, describing "huge explosions" that "shook the city." Reports of power outages and photos of fiery blasts rippled through the social media site.
The expanded strikes insert the U.S. military in Syria's vicious 3-year-old civil war for the first time, and open a significant new front for the latest U.S. war in the Middle East less than three years after Obama pulled all U.S. troops from Iraq.
Although Obama announced Sept. 10 that the U.S. goal was to "degrade and ultimately destroy" Islamic State, and that American airstrikes would expand into Syria, the overnight attack came as a surprise.
Pentagon officials had warned as recently as Sunday that airstrikes would be delayed until the White House could assemble a coalition of allies, especially Sunni Arab nations in the region, who would symbolically bolster the U.S. military effort.
But late Monday, Pentagon spokesman Rear Adm. John Kirby issued a statement saying the air war had moved west from Iraq into Syria, where an estimated two-thirds of Islamic State militants are based. Kirby said Gen. Lloyd J. Austin III, head of U.S. Central Command, had ordered the attack under authorization from Obama.
"I can confirm that U.S. military and partner nation forces are undertaking military action against ISIL terrorists in Syria using a mix of fighter, bomber and Tomahawk Land Attack Missiles," said Kirby, using a government acronym for Islamic State. "Given that these operations are ongoing, we are not in a position to provide additional details at this time."
Several news organizations reported that the partner nations included Saudi Arabia, the United Arab Emirates, Jordan and Bahrain, but U.S. officials did not confirm their participation. Most had previously signaled support for the U.S. effort, but did not say publicly what exactly they would provide.
Only France has publicly committed to launching airstrikes, but only in Iraq, not Syria. French warplanes attacked Islamic State positions in northern Iraq over the weekend.
The bombardment began the night before Obama heads to the United Nations, where he will chair a meet-
ing of the Security Council this week that will focus on efforts to hinder so-called foreign fighters from traveling to Syria to join the militants.
Administration officials had set the U.N. meetings as a deadline for firming up commitments from coalition members. The White House said it planned to use them to demonstrate broad opposition against the militants.
Obama called House Speaker John A. Boehner (R-Ohio) and Minority Leader Nancy Pelosi (D-San Francisco) to notify them, according to their spokesmen. Vice President Joe Biden briefed Sen. Dianne Feinstein, head of the Senate Intelligence Committee, and Defense Secretary Chuck Hagel notified Howard "Buck" McKeon (R-Santa Clarita), chair of the House Armed Services Committee, among others on Capitol Hill.
"Our men and women in uniform are once again striking an enemy that threatens our freedom," McKeon said in a statement. "This is one step in what will be a long fight against ISIL. With strong coalition partners, a capable military and a clear mission, it is a fight we can win."
Critics quickly lambasted the attacks as an unwarranted expansion of a U.S. military campaign that Obama said in August would focus only on protecting Americans in Iraq and on preventing genocide of religious minorities.
"Tonight's reported U.S. airstrikes in Syria were not to save those trapped on a mountain or to defend against a march on U.S. diplomatic personnel, but rather a clear escalation of American involvement in a regional conflict that the president himself says has no military solution," Stephen Miles, advocacy director of the Win Without War coalition, said in a statement.
Hagel told a congressional committee last week that a bombing campaign for Syria had been approved by his office, by the Joint Chiefs of Staff and by Gen. Austin, commander of U.S. forces in the Middle East. Obama reviewed the plan last Wednesday at U.S. Central Command headquarters in Tampa, Fla.
Hagel said the plan called for targeting Islamic State strongholds in northeastern Syria, including its logistical capabilities and infrastructure.
Islamic State, an Al Qaeda breakaway group, has taken control of vast tracts of Syria and Iraq in recent months. Its fighters have executed hundreds of Syrian and Iraqi soldiers, beheaded two American journalists and threatened to slaughter religious minorities in Iraq.
The Pentagon has launched about 190 airstrikes against the militants' positions and convoys in Iraq since Aug. 8, pushing them back from two strategic dams. The large-scale attack on Syria is a departure from those airstrikes, which chiefly targeted trucks, Humvees, checkpoints and mortar positions.
About 1,600 U.S. military advisors in Baghdad and Irbil are helping train Iraqi and Kurdish security forces, and conducting the airstrikes.
The new bombing campaign places the U.S. squarely within Syria's long-running civil war. Obama has said he would not seek authorization for any airstrikes from Syrian President Bashar Assad, whose government has sought with little success to drive Islamic State militants out of the large area they hold in northern and eastern Syria.
The Obama administration instead has been supporting more moderate Syrian rebels who have been seeking to oust Assad from power. Last week, Congress approved a $500-million plan to vet, train and arm about 5,400 Syrian rebels to help confront Islamic State militants. The training will be in Saudi Arabia.
The U.S. now finds itself combating one of the Assad government's most serious opponents only a year after the Obama administration considered launching airstrikes in Syria targeting not Islamic State but the Syrian government — intended as punishment after evidence emerged that the Syrians had used chemical weapons on civilians.
But the Assad government agreed to hand over many of its chemical weapons, and the campaign was never launched.