The attack, in which gunmen opened fire during a funeral at a Greek Orthodox church on Friday in the village of Hamoud in Karak governorate, about 120 kilometres southwest of the capital Amman, also wounded 40 others.
The shooting lasted several minutes, witnesses said.
Jordan’s Public Security Directorate said security forces located the three suspects early on Monday hiding in an abandoned house in Karak.
The suspects refused to surrender and opened fire on security forces, who returned fire and arrested all three after they were wounded, the directorate said in a statement carried on state media.
No security personnel were injured, and a number of firearms and ammunition were found in the suspects’ possession after their arrest.
“Terrorism has no place among us,” the directorate said, adding that the suspects had met their “just fate”.
The Public Security Directorate did not identify the suspects’ affiliation or say whether they belonged to any militant group.
Jordanian authorities have said the attack was carried out by “extremist terrorists”, but it was too early to determine whether they had links to known groups inside or outside Jordan.
There has been no claim of responsibility.
Interior Minister Mazen al-Faraya on Monday said authorities were reviewing the circumstances that led young people towards extremism and would hold accountable anyone found to have participated in the attack.
King Abdullah, a US partner in the fight against Islamist militant groups, has ordered security forces to respond with an “iron fist” to the rare attack on Jordan’s Christian minority.
Such violence is highly unusual in Jordan, a relatively stable state in the Middle East, though authorities say they have foiled several Islamist militant plots over the years. (Reuters)