A U.S. Predator drone was involved in the airstrike on Muammar Qaddafi's convoy Thursday in the moments before his death, a U.S. defense official told Fox News.

The official said the drone, along with a French fighter jet, fired on the "large convoy" leaving Qaddafi's hometown of Sirte. A French defense official earlier said about 80 vehicles were in the convoy -- the official said the strike did not destroy the convoy but that fighters on the ground afterward intercepted the vehicle carrying Qaddafi. He was later killed, reportedly in the crossfire between Qaddafi supporters and opponents as he was being transferred.

President Obama and other officials would not elaborate on the circumstances of Qaddafi's death. White House Press Secretary Jay Carney said only that U.S. and NATO actions helped Libyans reach this point.

But as some lawmakers continued to criticize the administration for its handling of the Libya operation, Obama pointed to the end of the Qaddafi regime as the close of a "long and painful chapter" for Libyans and defended the multilateral mission which began in March.

"Today we can definitively say that the Qaddafi regime has come to an end," Obama said. "This is a momentous day in the history of Libya."

Obama, speaking in the Rose Garden, said of Libyans, "You have won your revolution."

Obama said the NATO mission would soon be over; if so, the use of a Predator drone Thursday would mark a fitting end for U.S. involvement.

U.S. engagement in Libya consisted mostly of aerial missions. More than 70 U.S. aircraft were involved in the Libya operation -- throughout, the U.S. conducted a total of 145 Predator strikes in the country, in addition to thousands of other aerial missions. The United States has stepped up the use of Predator drones in several other countries, including Pakistan and Yemen. A drone was credited with killing American-born radical cleric Anwar al-Awlaki in September.

Though the attack Thursday started with an aerial strike, Qaddafi died of wounds suffered during his capture near Sirte, according to a spokesman for the National Transitional Council in Libya.

Lawmakers on both sides of the aisle hailed the news as a milestone, while turning their attention to the next step of helping Libyans form a new democratic government and ensure stability in a post-Qaddafi nation.

House Speaker John Boehner, in a written statement, called Qaddafi's death a "turning point in the Libyan people's pursuit of freedom."

Some lawmakers, though, continued to criticize Obama for his handling of the mission.

"He did the right things, he just took too long to do it," Sen. Marco Rubio, R-Fla., told Fox News. He later suggested that the operation would not have lasted as long as it did if the administration had gotten involved earlier and acted more decisively.

Throughout the mission, some lawmakers criticized Obama for letting NATO take the reins, while others complained that the president was moving forward without initially seeking permission from Congress.

But Obama on Thursday lauded the "unprecedented global response."

"Without putting a single U.S. servicemember on the ground, we achieved our objectives," Obama said. "We've demonstrated what collective action can achieve."

Asked Thursday if the president views Qaddafi's death as vindication for his approach, Carney said Obama "views this as a victory for the Libyan people."

Carney said the president made the "right decision" to work with U.S. allies. "I think this is a day not to engage in politics," he added.

Meanwhile, Obama and other officials cautioned that there will be "difficult days ahead" for Libya. Obama called on the new government to build an "inclusive and tolerant and democratic Libya that stands as the ultimate rebuke to Qaddafi's dictatorship."

He also called on Libyans to work with the international community to secure the "dangerous materials" left behind by the Qaddafi regime, a reference to the potentially thousands of weapons that are not yet accounted for.

Fox News' Jennifer Griffin and The Associated Press contributed to this report.