Arrest Made in Killing of Jordanian Intelligence Officers

AMMAN, Jordan — Three officers of the Jordanian intelligence service and two other employees of the service were killed on Monday in a Palestinian refugee camp near the capital, Amman, in what the government said was a terrorist attack.

The government has opened an investigation into the assault, which took place around 7 a.m. at an intelligence office in the Baqaa refugee camp, which was set up after the Arab-Israeli war of 1967 and is the largest in the country.

The attack, on the first day of the holy month of fasting known as Ramadan, struck in a country that has remained relatively stable despite being surrounded by conflicts.

“By attacking this office today, the terrorists want to send a message that they can attack at the heart of security in Jordan,” said Hassan Abu Hanieh, a Jordanian expert on Islamist groups.

No group claimed responsibility for the attack, and the authorities did not say how the victims were killed. Late Monday night, Mohammad Momani, a government spokesman, told the Petra news agency that one person had been arrested. Mr. Momani added that the investigation was continuing but that it was believed the killer acted alone.

Jordan is an important ally in the region for the United States, which has provided the country with more than $15 billion in economic and military aid since the 1950s.

Last year, the Obama administration and Jordan signed a three-year agreement in which the United States pledged $1 billion annually in total foreign assistance, subject to the approval of Congress, according to a report published by the Congressional Research Service.

Although terrorist attacks in Jordan are relatively rare, the country is constantly aware of the threat posed by Islamic extremists, notably the Islamic State.

“The attack was most likely carried out by a lone wolf or sleeper cells affiliated with the Islamic State,” Mr. Abu Hanieh said. “Most likely they targeted this particular spot because they thrive on creating divisions within society and want to wreak havoc.”

Last November, a Jordanian police officer killed five people, including two American trainers, at a compound near Amman before he was fatally shot. In March, a plot by the Islamic State to strike civilian and military targets in the country was thwarted.

Jordan has been involved in the United States-led aerial bombing campaign against Islamic State targets in neighboring Syria and Iraq since September 2014.

A Jordanian pilot was captured in December 2014 after his fighter jet crashed in Syria. A video released in February 2015 by the Islamic State showed the pilot being burned to death inside a cage.