A Chicago man accused of helping to plot an attack on a Danish newspaper that published incendiary cartoons of the Prophet Mohammed was "duped" by a friend, his lawyer told a judge Wednesday.

Tahawwur Hussein Rana, 48, is accused of using his immigration services business to provide a cover for David Coleman Headley's "surveillance" trips to Denmark and helping his plan the attack.

His lawyer argued that while he may have known that Headley was involved with a Pakistan-based radical Islamic group that has long fought Indian rule in divided Kashmir, Rana had no knowledge or involvement in the Danish plot.

- Mr Rana has been duped by Mr Headley - defense attorney Patrick Blegen told the court.

Blegen said the evidence presented in a criminal complaint -- which references emails and recorded conversations conducted in what prosecutors call a "code" -- is equally capable of showing that Rana "was not aware of Mr Headley's activities."

- There is no proof that allegations of murder or blowing up a building would ever be tied to Mr Rana - Blegen said during a preliminary detention hearing.

Blegen asked Judge Nan Nolen to release Rana on bond and said several family members were willing to put their homes up as security against his potential flight.

But prosecutors said the nature of the charges and Rana's strong ties abroad makes it too much of a risk to allow him to be released from jail pending trial even under tight supervision.

- It's a very serious offense presenting obvious danger to the community - assistant US attorney Daniel Collins told the court.

- The government is seeking detention. -

Judge Nan Nolen said she would require more time to consider the "very complex issue" of Rana's detention.

Headley, who told the FBI after his arrest that he toured the offices of the Jyllands-Posten newspaper in Copenhagen and Arhus "in preparation for an attack," is scheduled to appear on December 4 for a detention and a preliminary hearing.

Headley, 49, a US citizen who changed his name from Daood Gilani in 2006, was arrested by the FBI on October 3 at Chicago O'Hare airport before boarding a flight to Pakistan via Philadelphia, the authorities said.

Rana, a Canadian citizen born in Pakistan who has lived in the United States for nearly 15 years, was detained on October 18 at his Chicago home.