Al Qaeda's No. 2 leader Ayman al-Zawahiri said reprisals were possible in Denmark, Japan, Norway, and Sweden, in an audiotape released Tuesday. Coming in the wake of messages from Al Qaeda leader Osama bin Laden in March, the comments have raised concerns about the potential for new attacks in the West.

In some European countries, terror-threat levels have been elevated, with both Britain and Dutch leaders announcing in recent weeks that the potential for terror activity appeared to be increasing. That was attributed to more terrorists operating in Europe and to controversial depictions of Islam in cartoons and in film.

On Tuesday, a tape release by Osama bin Laden's top lieutenant called for strikes against the US-coalition in Iraq. The tape, for which a full translated transcript is not available, criticized the Palestinian group Hamas over "reported readiness to consider a peace deal with Israel" and Iran's "complicity" in the US assault on Afghanistan in 2001, reports the Agence France-Presse. Mr. Zawahiri also asserted that the "greed" at the root of global warming would make the world more sympathetic to Muslim "jihad" against the West. The voice on the tape could not be confirmed, but the two-hour message was the second of two installments in which Zawahiri responded to questions taken from extremist websites, the Associated Press reports.

Responding to a question of whether the terror group had plans to attack Western countries that participated in the U.S.-led invasion of Iraq and subsequent war, al-Zawahiri said, "My answer is: Yes! We think that any country that joined aggression on Muslims must be deterred."

The tape follows an assessment April 13 by Britain's home secretary, Jacqui Smith, describing the threat as "severe" and "growing," reports the BBC.

Ms Smith said: "We now face a threat level that is severe. It's not getting any less, it's actually growing….

"There are 2,000 individuals they are monitoring. There are 200 networks. There are 30 active plots.

"That has increased over the past two years. Since the beginning of 2007, 57 people have been convicted on terrorist plots."

Some of the elevated risk in Europe and to European forces abroad appears to stem from the lingering effects of right-wing Dutch lawmaker Geert Wilders's film that linked Islam's holy book, the Koran, with violence. The film, "Fitna," was released on the Internet March 27 and received 3 million page views before the website's host, British company LiveLeaks, shut down a link to the film, citing threats.

The video had been expected to incite the Muslim world, but its effects appeared subdued, especially compared with the violence that erupted after the publication of cartoons depicting the prophet Muhammad in 2006 that Muslims considered blasphemous. Those cartoons, first published by the Jyllands-Posten newspaper led to protests across the Muslim world, reported The Christian Science Monitor. The protests were reignited when one cartoon was published again in 2008 and a March recording attributed to Mr. bin Laden said that Europe would suffer attacks because of the cartoons.

While much of the film's impact appears to be taking place in Europe, where ongoing debate surround the freedom of expression, Dutch officials are taking precautions abroad. On April 17, reports Pakistan's Daily Times:

The Netherlands has moved its embassy in the Pakistani capital Islamabad over security concerns following the release of an anti-Koran film by a Dutch politician.

The Danish Foreign Ministry said Wednesday that it has evacuated its staff from embassies in Algeria and Afghanistan because of threats after newspapers reprinted the cartoon depicting the Muslim prophet Muhammad, reports Associated Press. That followed an April 20 attack on Dutch soldiers in Afghanistan, reports Reuters.

The Taliban said a deadly attack on Dutch soldiers in Afghanistan was in retaliation for an anti-Islamic film made by a politician from the Netherlands, a U.S. terrorism monitoring service said on Sunday....

The attack was one of "a sequence of missions taking revenge for the insulting film," the Taliban said in a message in Arabic on its website....

Earlier this year, Dutch officials had downplayed the risks of showing the film, saying the country had been engaged in diplomacy, reports Reuters.

"I don't think it will be risky for the military in Afghanistan," [Dutch Defence Minister Eimert van Middelkoop said] . "But we have to be alert, and we are."

Although Dutch diplomats met with Islamic leaders in the Mideast, who have conveyed the message that the film does not represent the country,the country's threat level, was raised, Reuters reports. And a new report by the head of the Dutch secret service cited more "jihadist activity" in the county, reports Radio Netherlands.

"As to the question of whether it is still safe in the Netherlands, I would say I still think the Netherlands is still safe. Having said that, I don't mean we aren't constantly on the alert for possible developments that could possibly lead to an attack. There has been both an increase in the actual threat and also an increase in the conceivable threat...."

Dutch officials had anticipated an uproar once the film was released. On the day of the release, however, one police spokesperson said the opposite was true, reported the Los Angeles Times. "In fact, it's quieter than usual here today. Sort of like a holiday."

Still, as Egyptian film critic Samir Farid told the Al-Ahram Weekly, the film highlights the polarized debate in both the Western and Muslim worlds. Mr. Farid sees hope in those who "are beginning to find the blizzard of European anti-Muslim artistic expression tiresome."

"Freedom of expression and secularism were once the hallmark of our own cultural heritage," Samir Farid, one of Egypt's leading film critics, told Al-Ahram Weekly. "In 1935 an Egyptian writer, Ismail Adham, published a book entitled Why I am an Apostate. Nobody called for his trial, let alone his death. Nobody called him an infidel. That was freedom of expression."

Farid laments the way in which, over recent decades, Muslim societies have become prey to the dictates of self-styled religious authorities who are seeking power. "When Westerners watch televised interviews with Osama bin Laden and Ayman El-Zawahri in which they celebrate the attacks of 11 September it should come as no surprise that some of them will go on to produce films, plays and books depicting Islam as a religion that glorifies violence....

"There is a schism over freedom of speech. There is the question of the politics of morality, or the lack of it."

Prior to the film's release, the German online newsmagazine Sign and Sight said Mr. Wilders seemed to have created in an ideal situation for himself – and a double bind for the Dutch government.

Wilders would consider the banning of his film by the Dutch government proof that the Netherlands is giving in to Islam. If the film does air and riots break out, this will prove Wilders' position that Islam is an intolerant religion.

While Europe continues to debate the freedom of expression, the European Union has also taken steps to strengthen its anti-terror rules, making it easier for police to shut down websites that incite violence or recruit for attacks, reports the International Herald Tribune. Still, the EU policing agency:

"Europol said this month that the number of arrests connected with terrorism doubled in the EU in 2007 from the previous year. The overwhelming majority of attacks carried out within the bloc, it said, were linked to separatist movements, rather than militant Islam."