US and European officials said Tuesday they have detected a plot to carry out a major, coordinated series of commando-style terror attacks in Britain, France, Germany and possibly the United States.
A senior US official said that while there is a "credible" threat, no specific time or place is known. President Obama has been briefed about the threat, say senior US officials.
Intelligence and law enforcement authorities in the US and Europe said the threat information is based on the interrogation of a suspected German terrorist allegedly captured on his way to Europe in late summer and now being held at Bagram Airfield in Afghanistan.
US law enforcement officials say they have been told the terrorists were planning a series of "Mumbai-style" commando raids on what were termed "economic or soft" targets in the countries. Pakistani militants killed 173 people with guns and grenades during the 2008 attacks in Mumbai, India.
In testimony before Congress last week, Homeland Security Secretary Janet Napolitano said, "We are all seeing increased activity by a more diverse set of groups and a more diverse set of threats."
Officials in France have put the country on high alert for a terror attack and authorities in Paris shut down the Eiffel Tower for the second time in two weeks today after what was termed a "false alarm."
No bomb was found but officials in France are taking no chances, given what they believe is a very real threat.
"We currently have reached a spike in the threat of an attack, which is unquestionable," said the head of the French National Police last week. He also said France was at particular risk from al Qaeda's North African affiliate.
The new threat to France, and to Germany and Britain and the U.S., is coming from Pakistan, according to intelligence officials. The captured German reportedly said several teams of attackers, all with European passports, had been trained and dispatched from training camps in Waziristan and Pakistan. Officials say the German claimed the attack plan had been approved by Osama Bin Laden.
US intelligence officials said they believed an attack on American soil was more likely to come from terrorists connected to the al Qaeda group in Yemen, known as AQAP, al Qaeda of the Arabian Peninsula.
But an official of the New York Police Department said while the most specific information was about Europe, NYPD intelligence officers were following the new information closely. "Nobody here is letting their guard down, the NYPD is watching," the official said.
Germans Training in Al Qaeda-Connected Camps
In the last four years, dozens of German citizens have been recruited to train in al Qaeda-connected camps in Pakistan, according to US and German law enforcement officials. German language jihadi videos on the internet help to attract more trainees.
"Some are German converts, many are Turks, many are Arabs," said Guido Steinberg, a counter-terrorism analyst at the German Institute for International and Security Affairs. "Right now we already have the first Afghans and even Iranians in these circles. It's a very mixed bunch of people -- quite international."
"The American authorities are extremely nervous about what is going on, the Germans are extremely nervous about what's going on," said Steinberg.
"The advantage, of course, is the passport," said Steinberg, "because with the German passport it's a lot easier to travel."
Travelers with German passports do not require a visa to enter the United States. Officials now believe at least one team of German jihadists was dispatched to Europe over the summer, travelling on German passports.
Steinberg said that many of the German jihadis who train in Pakistan are killed, "but those who come back are a threat. "And they are a threat not only to Germany," added Steinberg, "but also to our allies and especially the U.S. because they are extremely anti-American."
Steinberg said the Germans were recruited from mosques in Berlin, Bonn and Hamburg, including the same mosque in Hamburg where Mohammed Atta and other 9/11 hijackers gathered. German authorities shut down the Taiba mosque in Hamburg, previously known as the al Quds mosque, in August.
"Young men were being turned into religious fanatics there," said Christoph Ahlhaus, secretary of the interior for the city of Hamburg at the time.
"Hamburg cannot become a cradle for Islamists capable of violence," said Ahlhaus.
Steinberg said it was "quite shocking" that the former al Quds mosque was still producing jihadis. "There is a certain amount of continuity in German jihadism,' said Steinberg.
Drone Strikes Along Pakistan Border
US officials said the CIA has been in frequent touch with European counterterrorism officials since the threat emerged this summer.
The threat may help explain the increase in U.S. air strikes in the mountainous area along the Pakistani and Afghan border.
There have been at least 70 attacks this year alone, with new ones announced each day, as General David Petraeus explained in an interview with Martha Raddatz of ABC News.
"The sanctuaries and safe havens, again, there will have to be more done about them," said Gen. Petraeus. "There were will have to be more pressure on them, no question."
In a statement to ABC News, Director of National Intelligence James Clapper declined to discuss the threat.
"We are not going to comment on specific intelligence, as doing so threatens to undermine intelligence operations that are critical to protecting the U.S. and our allies," said Clapper. "As we have repeatedly said, we know al Qaeda wants to attack Europe and the United States. We continue to work closely with our European allies on the threat from international terrorism, including al Qaeda. Information is routinely shared between the U.S. and our key partners in order to disrupt terrorist plotting, identify and take action against potential operatives, and strengthen our defenses against potential threats."
The FBI declined to comment.