NEW YORK — Zambian authorities have detained a man sought for questioning in this month's deadly London bombing plot, as well as for his alleged role in setting up a terrorist training camp in Oregon, U.S. officials said yesterday.

Haroon Rashid Aswat, 30, a British citizen of Indian descent, piqued the interest of investigators when they discovered that about 20 calls had been placed from his cellphone to some of the men who set off bombs on London's underground and a bus July 7, killing 52 people.

Two Pakistani sources said last week that Aswat had been arrested there. But other Pakistani officials subsequently denied that, and British and Indian officials in recent days have said the arrest in Pakistan was a case of mistaken identity involving a Briton with a similar name.

Two U.S. anti-terror officials, speaking on condition of anonymity because of the ongoing investigation, said Aswat was arrested in Zambia, but they did not elaborate on the circumstances of his capture or the reasons for his travel there. Aswat has lived in South Africa and traveled extensively on the continent; Zambia has a sizable Indian community.

One of the U.S. officials said British and U.S. anti-terror investigators had gone to Zambia after Aswat's detention last week and were in conversations with each other and Zambian officials to determine where it would be best to prosecute Aswat.

Aswat reportedly grew up in the same part of northern England as three of the July 7 bombers. He has been characterized by U.S. law-enforcement officials as an emissary of Abu Hamza al Masri, a radical, one-eyed Muslim cleric in London who repeatedly has denounced the United States.

Aswat first came to the attention of U.S. authorities several years ago, when he surfaced as a close ally of James Ujaama, a Seattle man who proposed building a training camp for militant Islamists in Bly, Ore., near the California border.

Court records in New York and Seattle, and interviews with federal authorities in both cities, reveal numerous details about Aswat's alleged activities in the United States and his association with Abu Hamza and his followers.

One U.S. federal law-enforcement official said of Aswat: "He has gotten around, and he's been someone of interest for some time."

In 1999, Abu Hamza sent Ujaama back to the United States to begin putting together the training camp in Oregon. After a remote property was decided upon near Bly, Abu Hamza allegedly sent Aswat to follow up on progress there.

According to court records and interviews, Aswat flew to New York on an Air India flight from London in November 1999. He then visited the Bly ranch, but he was dismayed by the conditions he found and eventually abandoned the idea of using the property as a training camp, according to sources who spoke to The Seattle Times.

Before returning to London, Aswat spent time in Seattle in the winter of 2000, reportedly living at the now-defunct Dar-us-Salaam mosque.

Serrano reported from New York, Miller from Washington and Rotella from London. Seattle Times staff reporter Hal Bernton also contributed to this report.