Tahawwur Rana, a Canadian citizen, already faces charges he helped aid a plot to attack a Danish newspaper. (Verna Sadock/Associated Press)

A Canadian man accused of aiding a plot to attack a Danish newspaper is now facing charges that he helped plan the 2008 attack in Mumbai that killed more than 160 people.

Tahawwur Hussain Rana already faces charges in the United States of conspiracy to provide material support to an overseas terrorism conspiracy in connection with the plot to attack a Danish newspaper that published cartoons about the Prophet Muhammad.

An indictment unsealed in Chicago on Thursday alleges for the first time that Rana helped plan the Mumbai massacre.

Ten armed assailants launched a three-day attack on two luxury hotels, a hospital, a Jewish centre and a train station in the city, killing 166 people, including two Canadians.

Rana was charged with three counts of lending material support to a terrorist conspiracy.

Rana, a Canadian businessman originally from Pakistan, has primarily resided in Chicago but has an immigration services business with offices in Toronto, Chicago and New York.

Defended by family

Members of Rana's family, some of whom live in the Ottawa region, have defended Rana as a "peaceful person." Rana has maintained he knew nothing about the Mumbai attack.

But U.S. prosecutors say Rana knew in advance of the attack and sent congratulations to its perpetrators for their planning.

Also named in the indictment is American David Coleman Headley, also of Chicago.

Headley, who changed his name from Daood Gilani in 2006, was arrested along with Rana in November last year for his alleged role in the plot to attack Morgenavisen Jyllands-Posten, a Danish newspaper that in 2005 published cartoons depicting the Prophet Muhammad.

U.S. investigators allege Rana used his immigration business to help Headley obtain entry into India, where Headley allegedly began mapping potential targets in advance of the Mumbai attack.

With files from The Canadian Press