The US embassy in Amman said security had been stepped up at malls, foreign embassies and other locations across Jordan after Friday's attack on a church in Jordan that authorities described as a terrorist act by extremists.
Seven people were killed and dozens were injured when gunmen opened fire during a funeral at a Greek Orthodox church in Karak governorate, the head of Jordan's Public Security Directorate said.
There was no immediate claim of responsibility.
Such attacks are extremely rare in Jordan, though authorities in the US ally say that in recent years they have repeatedly foiled attempted attacks by Islamist militants.
Jordanian officials have not yet confirmed links to Islamist groups
Authorities said they are still searching for the attackers, adding it was too early to determine whether they had links to known groups inside or outside Jordan.
"This is a result of a terrorist ideology and blind extremism and we will not allow society to go down this path," Prime Minister Jafar Hassan said in a post on X/Twitter hours after the violence.
Jordan's King Abdullah, a major US partner in the fight against militant Islamist groups, visited Karak hours after the attack and said the perpetrators would be punished "with an iron fist."
Christians make up a minority of Jordan's population. The country is home to several biblical sites that attract Christian pilgrims from around the world.
Jordan has been among US allies in the region to be hit by Iranian attacks this year after the US and Israel launched strikes against Iran in February.