Four men will be charged Thursday in connection with a terror plot against a Danish newspaper that published cartoons of the Prophet Mohammed, the nation's authorities said.
Three men arrested in Copenhagen, Denmark, on Wednesday after arriving from Sweden are believed to be "connected to international terrorists," Denmark's intelligence service said.
One of the men arrested is a Tunisian national while at least two have Swedish citizenship, including one of Lebanese origin. Another man arrested in Denmark, described as a 26-year-old asylum seeker from Iraq, is thought to have provided the alleged plotters with a place to stay in Herlev near Copenhagen.
A fourth man arrested is believed to have visited Afghanistan and Pakistan last year, officials said.
Swedish intelligence sources say a fifth suspect, a 37-year-old Swedish citizen of Tunisian origin, was arrested in Stockholm.
The group was allegedly planning a gun attack on the offices of the Danish newspaper, which published the cartoons in 2005 and reprinted them in 2008.
"Our assessment is that their plan was to try to get access to the Jyllands-Posten building and carry out a Mumbai-style attack," the head of Denmark's intelligence service, Jakob Scharf, said Wednesday. He described the suspects as militant Islamists.
Pakistani terrorists launched gun attacks on hotels and other targets in the Indian city of Mumbai in 2008, killing more than 170 people.
Denmark's Justice Minister Lars Barfoed said the plot constituted "probably the most serious terror attempt in Denmark so far."
The men had been under surveillance for months, and were among 200 radicals identified in a recent Swedish intelligence report, according to intelligence sources in Scandinavia. Sweden raised its terror alert in October. An estimated 300,000 Muslims live in Sweden.
Denmark's intelligence service said the men had rented a car near Stockholm and driven to Denmark with a sub-machine gun, silencer and ammunition, with the intent of carrying out an attack by the New Year. Swedish authorities say the car was followed by security police who knew there were weapons in the car.
Danish intelligence sources say they are not ruling out a connection between the plotters and Islamist extremists in Scandinavia who were in contact with American citizen David Headley. Headley said he had visited Sweden and Denmark last year. Headley was arrested in Chicago in October 2009 as he was about to leave for Pakistan. He later confessed to planning the Mumbai attacks and to carrying out a reconnaissance of the offices of the newspaper with the intent of launching a terror attack. Video of the newspaper's offices was found in his luggage.
According to an interview of Headley by India's National Investigation Agency obtained by CNN, he met with a Moroccan living in Sweden in the summer of 2009. The man, known only as Farid, was an associate of a senior al Qaeda commander, Ilyas Kashmiri, whom Headley had met while in Pakistan.
"Farid told me he was being continuously watched and he was not available for Denmark project," Headley is quoted as telling Indian investigators.
There have been several plots against the newspaper building. Earlier this year, a Belgian of Chechen descent was injured in Copenhagen when a bomb he was carrying blew up in a nearby hotel. He is awaiting trial.
Danish counter-terrorism officials say it's unclear whether Islamic radicalization is growing in Denmark, but believe extremists are more prepared to use violence.
Intelligence analysts point out that the men alleged to have been involved in this latest plot are between ages 26 and 43, and are not the alienated youth often associated with such plots.