Chicago, April 26 (IANS) US federal prosecutors have added four top Pakistani terrorists tied to Lashkar-e-Taiba (LeT) as accused in the case against Pakistani-Canadian LeT operative Tahawwur Rana for helping to plot the November 2008 Mumbai terror attacks.

The four identified as Sajid Mir, Abu Qahafa, Mazhar Iqbal and "Major Iqbal" were charged Monday in US District Court in Chicago, though none of them is in US custody. All four are charged with one count of conspiracy to murder and maim in India, while Mir, Abu Qahafa and Mazhar Iqbal additionally are charged with conspiracy to bomb public places in India.

They also face six counts of aiding and abetting the murder of US citizens in India, which carry maximum sentences of death or life imprisonment.

The revised indictment comes three weeks before the scheduled May 16 trial of Rana, a Canadian citizen who is accused of using his First World Immigration Services business to provide cover to Pakistani-American David Coleman Headley, to scout targets for the Mumbai attack.

Headley, the son of an American mother and Pakistani father, pleaded guilty in March 2010 to 12 criminal counts including aiding and abetting the murder of Americans in Mumbai and agreed to cooperate with the prosecution in a plea deal to escape the death penalty.

Mir, also known as "Wasi," aka "Ibrahim," and "Sajid Majeed", who reportedly joined the Pakistan based terror outfit LeT at age 16, allegedly worked as Headley's handler for two years.

The new indictment says that "during the course of attacks in Mumbai, the attackers were in telephonic contact with defendants Sajid Mir, Abu Qahafa and Mazhar Iqbal, all of whom were then located in Pakistan."

"More specifically, during the course of the attacks, the attackers were advised to, among other actions, kill hostages, set fires and throw grenades," the indictment said.

"Sajid Mir also sought to arrange the release of a hostage in exchange for the release of a captured attacker."

It also accused Mir of working with Headley to plan a terrorist attack on a Danish newspaper, which in 2005 published cartoons of Prophet Mohammed touching off

There is also a warrant for Mir's arrest in India. During the Mumbai attack, Indian police intercepted phone calls between Mir and his terror teams in Mumbai.

Terrorist group Harakat ul Jihad al Islami leader Ilyas Kashmiri and retired Pakistani military man Abdur Rehman Hashim Syed also were charged in a previous indictment but their whereabouts are unknown.

Rana faces life imprisonment if convicted on the charges he provided material support to the Mumbai attackers.