Jordanian security forces rounded up Islamic activists today for questioning about Monday's killing of an American diplomat, and the Jordanian ruler, King Abdullah, warned that his country "will not tolerate evil extremists."

Officials and news reports said the security forces detained militants across the kingdom, searching Palestinian refugee camps and sections of Amman, the capital city where the American aid official, Laurence M. "Larry" Foley, was gunned down as he walked from the front door of his house to his car in a well-to-do residential neighborhood.

In Maan, a southern Jordanian city regarded as a stronghold of Muslim extremism, a fundamentalist leader was reportedly wounded during a shooting that broke out while he was being taken into custody. The Reuters news agency said two policemen were wounded in addition to the militant leader, identified as Mohammad Ahmad Chalabi, also known as Abu Sayaff.

Officials gave no estimate of the total number detained. But one security official told reporters dozens were brought in for questioning.

"No one has been arrested yet," said Mohammed Adwan, a government spokesman. "The police are questioning all sorts of people in the vicinity, and otherwise."

Foley, 60, was shot at least seven times at point-blank range by a masked assailant in the driveway of his home. The shooter escaped on foot, although Jordanian officials said the planning apparent in the assault indicated the shooter may have had accomplices.

Investigators and U.S. officials said the killing was presumed to be an act of political terrorism, absent any indication of robbery or other motives.

Foley, like many U.S. diplomats and embassy support personnel, was widely known in his neighborhood as an American. Beyond the usual social knowledge shared by neighbors, his car bore color-coded diplomatic license plates and a security firm associated with the embassy routinely sent mobile patrols past his house, recently parking for hours at a time.

Jordanian officials said investigators were seeking more witnesses to the attack. Foley's wife, Virginia, reportedly saw the assailant fleeing after the shooting. But the specific motive behind the attack remained a matter of speculation. Jordanian officials continued to characterize the attack, by dint of the publicity it attracted, as an assault on their country, a traditionally Western-leaning kingdom that has received $3.4 billion in U.S. aid over the last decade.

In recent months, Jordan has grown closer to the United States even as tensions between the Arab world and the United States have increased. Two main engines of that tension flank the country. Iraq, which uses oil supplies to solicit close ties with Jordan, lies immediately to the east. During a recent visit to Amman, a senior Iraqi official called for Arabs to strike at the United States should it proceed with military action aimed at deposing or disarming President Saddam Hussein. And to the west lie Israel and the Palestinian territories of the West Bank and Gaza Strip. Millions of Palestinians and refugees reside within Jordan's borders, making up more than half its 5 million inhabitants.

Abdullah, during a condolence call to the U.S. Embassy here, vowed that Foley's killer or killers would be caught. He dismissed the suggestion that the attack would foment dissension in the kingdom.

"If anything, I think it makes us stronger," said the monarch, who was accompanied by his wife, Queen Rania. "I think it binds people together."

Authorities and analysts gave little credence to a claim of responsibility made by an obscure group to a London-based Arabic-language newspaper. The daily Al-Quds Al-Arabi quoted the group, which calls itself Honorables of Jordan, as saying the U.S. Agency for International Development official was cut down because of U.S. support for Israel and "bloodshed in Iraq and Afghanistan."

Jordanian officials questioned the authenticity of the claim and said the very existence of the group, which took responsibility for at least one earlier shooting in Amman, remains an open question.