Three U.N. workers kidnapped in Afghanistan four weeks ago were released unharmed Tuesday, a day after a string of raids by U.S. and Afghan security forces.

The release was a relief to foreign aid workers and U.N. staffers among Kabul's 2,000-strong expatriate community, under virtual lockdown since the kidnapping. Large tracts of the country are already off-limits to relief workers because of a stubborn Taliban-led insurgency.

Philippine diplomat Angelito Nayan, British-Irish citizen Annetta Flanigan and Shqipe Hebibi of Kosovo were seized at gunpoint from a U.N. vehicle on Oct. 28 in Kabul.

They were first foreigners abducted in the Afghan capital since the Taliban (search) fell three years ago, and their abductions raised fears that the Afghan capital could become prey to the kind of deadly kidnappings by insurgents that have plagued Iraq.

"They are out," U.N. spokesman Manoel de Almeida e Silva said. "I'm told they are in good spirits and they seem to be fine."

Afghan Interior Minister Ali Ahmad Jalali said the trio were "abandoned in one location inside Kabul" at around 6 a.m. Tuesday.

Jalali said discussions had been held with the kidnappers, whom he declined to identify, but insisted no deal was done and that the releases were unconditional.

"None of the hostage-takers conditions have been met," he told a news conference. "All those people who had a hand in this — directly or indirectly — will be brought to justice."

Afghan officials have said they believe a criminal gang carried out the abductions, and have said that negotiations centered on a ransom demand.

Jalali said it was "possible" that a Taliban-linked group which has claimed responsibility for the kidnappings had hired some criminals to abduct the three, who helped organize the country's Oct. 9 presidential elections.

The group, Jaish-al Muslimeen (search), or Army of Muslims, had demanded that Afghan and U.S. authorities free jailed comrades.

"I cannot say they were not involved," Jalali said.

The foreigners were freed a day after U.S. and Afghan forces raided two houses in downtown Kabul on Monday and detained 10 people in connection with the abductions.

Most of the detainees were released after being questioned, an Afghan intelligence official said, and it was not clear if the arrest of a doctor who worked at a U.N. clinic in the city had hastened the hostages' release.

Jalali also said one person was killed and four injured in another police operation linked to the kidnapping north of Kabul on Monday. He declined to give details, saying it could endanger efforts to round up more suspects.

Officials said the three U.N. workers underwent medical examinations at a NATO base in Kabul that showed all were well and were then given time to call relatives and friends and to relax.

"It's a very happy moment, but also a very private moment," said Almeida e Silva, the U.N. spokesman. He said all three would travel home to their families "very soon."

Philippine Foreign Undersecretary Jose Brillantes told Manila radio DZMM from Kabul that he talked with Nayan.

He said Nayan spoke by phone to his sister in Manila and had an "emotional telephone conversation" with President Gloria Macapagal Arroyo (search). He "was a bit apologetic" that everyone had to go through so much trouble, Brillantes said.

The British government released a statement by Flanigan's family expressing their joy at the peaceful end to the crisis and their thanks to the authorities.

"After all the terrible anxiety of the last 27 days it is an incredible relief to know that Annetta is safe and well."

Syed Khalid, a spokesman for Jaish-al Muslimeen, told The Associated Press on Tuesday it had freed the hostages overnight against an "assurance that the release of our 24 people would begin today."

His claims could not be verified. Silvestre Afable, a Philippine government spokesman, also insisted there was no prisoner-for-hostage exchange.

U.S. Ambassador Zalmay Khalilzad hailed the releases as a "major defeat to terrorists who wanted to export an Iraq-style of hostage-taking in Afghanistan."

Khalilzad said the Afghan government, people, the United Nations, as well as NATO peacekeepers and U.S.-led coalition forces had worked together to bring about the releases, sending "an important message to those who wish to disrupt the new Afghan democracy."

Jalali appealed to Afghanistan's international backers not to lose their nerve in the face of the kidnapping which "must not be repeated and will never be tolerated."

"We hope it will not discourage the resolve of the international community to continue their work to assist the Afghan people in the pursuit of lasting peace and security," he said.