DAMASCUS, Syria — Hundreds of Syrians gathered at landmark squares in the Syrian capital Saturday, honking their car horns, flashing victory signs and waving Syrian flags in scenes of defiance that followed unprecedented joint airstrikes by the United States, France and Britain.

A few hours earlier, before sunrise, loud explosions jolted Damascus and the sky turned orange as Syrian air defense units fired surface-to-air missiles in response to three waves of military strikes meant to punish President Bashar al-Assad for his alleged use of chemical weapons.

Associated Press reporters saw smoke rising from east Damascus and what appeared to be a flame lighting up the sky. From a distance, U.S. missiles hitting suburbs of the capital sounded like thunder. Shortly after the one-hour attack ended, vehicles with loudspeakers roamed the streets of Damascus blaring nationalist songs.

“Good souls will not be humiliated,” Syria’s presidency tweeted after the airstrikes began.

Immediately after the attack, hundreds of residents gathered in Damascus’ landmark Omayyad square, celebrating what they said was the army’s success in shooting down or derailing some of the missiles. Many waved Syrian, Russian and Iranian flags. Some clapped their hands and danced, others drove in convoys, honking their horns.

“We are not scared of America’s missiles. We humiliated their missiles,” said Mahmoud Ibrahim, waving a Syrian flag. The crowd then moved toward the nearby Damascus University, where pro-government fighters danced, waving their automatic rifles over their heads.

President Trump announced Friday night that the three allies had launched military strikes to punish Assad for alleged chemical weapons use and to prevent him from doing it again. Trump said Washington is prepared to “sustain” pressure on Assad until he ends what the president called a criminal pattern of killing his own people with internationally banned chemical weapons.

The Syrian government has repeatedly denied any use of banned weapons. A fact-finding team of inspectors from the international chemical weapons watchdog was in Damascus and had been expected to head to the town of Douma on Saturday, scene of the suspected chemical weapons attack that killed more than 40 people.

The seemingly limited strikes with no apparent future strategy for how to deal with the wider civil war was a cause for celebration by Assad supporters but criticized by the Syrian opposition.

Mohammad Alloush, spokesman for the Army of Islam rebel group, called the airstrikes a “farce” in a Twitter posting. Nasr al-Hariri, a senior opposition leader, said Syrians need a strategy that leads to a political solution to “save it from the brutality of the Syrian regime.”