Pakistani police got a major break in the Daniel Pearl kidnapping case Tuesday afternoon when the chief suspect in the Wall Street Journal reporter's abduction was taken into custody.

Interior Ministry secretary Tasneem Noorani told reporters that Ahmad Omar Saeed Sheikh, a London-born Islamic militant, had been arrested in the eastern city of Lahore, near the Indian border. He did not give further details.

Jamil Yousuf, head of a citizen-police liaison committee involved with the investigation, quoted Saeed as saying about Pearl, "He's alive. He's OK."

Sources told Fox News that house-to-house searches were being conducted in the port city of Karachi Tuesday evening. Other arrests were reported in Karachi, Rawalpindi and other major Pakistani cities Tuesday.

Pearl's whereabouts remained unknown. He was kidnapped Jan. 23 in Karachi and the last known communication from his kidnappers was received Jan. 30.

Saeed's detainment "is a significant achievement in the case," Noorani said, adding that the suspect would be transferred to Karachi for interrogation. "We have to wait" to learn more about Pearl, Noorani added.

Yousuf said the key break came Monday night with the arrest of a suspect in the capital of Islamabad who gave crucial information. He did not elaborate.

The arrest came one day before Pakistani President Gen. Pervez Musharraf was to meet U.S. President George W. Bush in Washington. The Pearl case has embarrassed Musharraf's government, which took significant risks in so strongly allying itself with the United States against Pakistan's former Taliban allies in Afghanistan.

Pakistan is also seeking American monetary and military assistance in fighting its own hard-line Islamic militants.

Lonnie Kelley, spokesman for the U.S. Consulate in Karachi, said American officials were trying to confirm that Saeed has been arrested.

"We are looking into it, but nothing on Daniel yet," he said.

Steve Goldstein, a vice president and spokesman for Dow Jones, the Wall Street Journal's parent company, declined to comment on whether the arrest revealed new information about Pearl's abduction.

"We continue to remain hopeful," Goldstein said in a telephone interview. He also declined to comment on specifics of the case.

A team of police officers from Sindh province, which includes Karachi, had been in Lahore, part of Punjab province, searching for Saeed for the last few days, the government-run news agency Associated Press of Pakistan reported Tuesday.

Police identified Saeed as the prime suspect in the case after arresting three men suspected of sending e-mails that announced Pearl's kidnapping.

One of the three, who was found to have the sent e-mails on his laptop computer, told investigators that he got them from Saeed, police said. The other two reportedly said they had met Saeed in Afghanistan.

The three were charged with kidnapping Tuesday and ordered jailed for two more weeks They were brought to Sindh province's High Court in an armored personnel carrier surrounded by 20 machine-gun toting policemen wearing helmets and bulletproof vests. The suspects were chained together at the waist, their heads and faces covered by shawls and bath towels.

The trio had been due in court Monday but proceedings were delayed after officials decided that anti-terrorism judge Shabir Ahmed, not a civil one, should hear the case.

Pearl, the Journal's South Asian bureau chief, was abducted on his way to a Karachi restaurant to meet with Islamic extremists. He hoped they would provide information about e-mails exchanged by Pakistani militants and Briton Richard C. Reid, the so-called "shoe bomber" arrested on a Paris-to-Miami flight in December with explosives in his sneakers.

Decrypted files on a computer used in a Kabul office of Usama bin Laden's Al Qaeda organization detailed the movements and passport status of an operative whose circumstances and details matched Reid's, although the files did not mention the operative's real name.

Four days after Pearl's disappearance, an e-mail sent to Pakistani and international media showed photos of him in captivity and demanded that the United States repatriate Pakistanis captured in Afghanistan and now detained at the U.S. naval base in Guantanamo Bay, Cuba.

A second e-mail sent Jan. 30 said the 38-year-old reporter would be killed in 24 hours. That was the last known message from his captors.

The 27-year-old Saeed, the arrested prime suspect, lived a life of privilege in Britain before a documentary film about the Bosnian civil war drew him to the Balkans, where he became involved with militant Islamism. In 1994, he was sent to prison in India for having kidnapped four Western tourists, all of whom were released unharmed.

At the end of 1999, Saeed was released as part of a trade for the passengers of an Indian Airlines jet that had been hijacked to Kandahar, Afghanistan. That hijacking was thought to have been carried out by the Harakat ul-Mujahedeen, a Pakistan-based militant group involved in guerrilla and terror attacks in the Indian part of the disputed province of Kashmir.

The so-called "American Talib," John Walker Lindh, has reportedly stated that the Harakat gave him basic military training before he asked to leave to fight with the Taliban in Afghanistan.

A deserted Harakat office in Kabul contained papers naming another American, Hiram Torres of New Jersey, who disappeared in Pakistan in 1998 after having converted to Islam, as a recruit. Also in the office were boarding passes and passenger lists from the hijacked Indian Airlines flight.

India has named the Harakat as one of the two groups responsible for an attack on the Indian Parliament on Dec. 13 that killed eight people.

Fox News' Paul Wagenseil and the Associated Press contributed to this report.