Usama bin Laden's (search ) operatives still use this freewheeling city as a logistical hub three years after more than half the Sept. 11 hijackers flew directly from Dubai to the United States in the final preparatory stages for the attack.

The recent arrest of an alleged top Al Qaeda (search ) combat coach is the latest sign that suspected members of the terrorist organization are among those who take advantage of travel rules that allow easy entry. Citizens of neighboring Gulf states such as Saudi Arabia can come to Dubai without visas, which other nationalities can get at the country's ports of entry.

Once here, it's easy to blend in to what has become a cosmopolitan crowd.

The Emirates is home to an estimated 4 million people, and nearly 75 percent of them are foreigners. In Dubai, expatriates of all nationalities are catered to, from concerts by top Western musicians to cricket and rugby matches to a German-styled Oktoberfest.

The expatriates, mostly from the Indian subcontinent and the Arab world, are employed in the real estate, insurance, tourism and banking sectors. Westerners, numbering in the tens of thousands, are employed as military advisers and oil specialists.

While the Emirates has taken concrete steps to fight terrorism since Sept. 11, 2001 — including making high-profile arrests, passing an anti-money laundering law, and imposing close monitoring procedures on charity organizations — the characteristics that make it an ideal place for legitimate business also attract militants and others with suspect motives.

In August, Pakistani Qari Saifullah Akhtar, suspected of training thousands of Al Qaeda fighters for combat, was arrested in the Emirates and turned over to officials in his homeland, authorities in Pakistan announced.

Emirates authorities have refused to comment on Akhtar's arrest. They were similarly tightlipped in 2002, when the United States announced the arrest of Abd al-Rahim al-Nashiri, the suspected mastermind of the 2000 bombing of the USS Cole (search ), which killed 17 U.S. sailors.

It was a month before Emirates officials confirmed al-Nashiri had been arrested here. Then they said he had been planning to attack "vital economic targets" in the Emirates that were likely to inflict "the highest possible casualties among nationals and foreigners."

The Saudi-born al-Nashiri, one of six Cole defendants in an ongoing trial in Yemen, is in U.S. custody at an undisclosed location. Besides the Cole attack, he is suspected of helping direct the 1998 bombings of U.S. embassies in Kenya and Tanzania, U.S. officials say.

With open borders, multiethnic society and freewheeling business rules, the Emirates remains vital to Al Qaeda operations, said Evan F. Kohlmann, a Washington-based terrorism researcher.

Dubai still "plays a key role for Al Qaeda as a through-point and a money transfer location," Kohlmann said, although he also noted the country could be working to combat such activity with "an aggressive but low-profile intelligence strategy."

Al Qaeda isn't the only organization that has found Dubai useful. The father of Pakistan's nuclear program, Abdul Qadeer Khan, has acknowledged heading a clandestine group that, with the help of a Dubai company, supplied Pakistani nuclear technology to Iran, Libya and North Korea.

Emirates officials refused to discuss the country's latest steps to combat terror.

Dia'a Rashwan, an Egyptian expert on militant groups, said trumpeting developments such as the arrest of Al Qaeda suspects could be misread as serving the United States when the Emirates, led by its President Sheik Zayed bin Sultan Al Nahyan, cultivates an image as a champion of Arab causes. The Emirates nonetheless has a close relationship with Washington.

Rashwan said the reticence also could stem from fear that saying too much could cause "panic among the huge expatriate community, which is proportionally the largest in the Gulf."

Kohlmann said if more Al Qaeda suspects are arrested in the Emirates, the network might retaliate with a strike here, perhaps on a U.S. mission or military target.

While the country has not been singled out as a target by Al Qaeda, the United States issued a warning in June that it had "information that extremists may be planning to carry out attacks against Westerners and oil workers in the Persian Gulf region, beyond Saudi Arabia."

Security is tight in the Emirates, but not visible, and violent crimes are uncommon.

"The United Arab Emirates is considered a safe haven for everybody," said Emirates analyst Abdulkhaleq Abdulla. "It has not yet got entangled in any of the violence that other countries around it have experienced and it wants to keep that image."

Shortly after the Sept. 11, attacks, U.S. authorities said the United Arab Emirates, especially the commercial hub Dubai, was a major transit and money transfer center for Al Qaeda.

A new report dated Aug. 21 by the U.S. commission investigating the Sept. 11 attacks provided the most detail yet on the extent to which the hijackers used Dubai as a travel hub.

According to the U.S. government, 13 of the 19 hijackers entered the United States between April 23 and June 29, 2001. And 11 of those late-arrivers — who were Saudi citizens and primarily the "muscle" for the hijackings — went through Dubai, according to the report.

The hijackers traveled in groups of two or three, taking off from Dubai and arriving at airports in Miami, Orlando, Fla., or New York City, the report said.

As for the money trail, Bin Laden's alleged financial manager, Mustafa Ahmed al-Hisawi, received at a Dubai bank a transfer of $15,000 two days before the Sept. 11 attacks and then left the Emirates for Pakistan, where he was arrested last year.

Marwan Al-Shehhi (search ), an Emirates citizen and one of the hijackers, received $100,000 via the United Arab Emirates. Another hijacker, Fayez Banihammad, also was from the Emirates.

About half of the $250,000 spent on the attacks was wired to Al Qaeda terrorists in the United States from Dubai banks, authorities said. Al Qaeda money in Dubai banks also has been linked to the 1998 U.S. Embassy bombings in Kenya and Tanzania.