UPDATED: 5/23/2011 1:05 p.m.

CHICAGO (CBS) — A Pakistani-American who has pleaded guilty to laying the groundwork in the 2008 Mumbai attacks says he first started training with a Pakistani militant group more than a decade ago and it was his understanding that the group and the country’s main intelligence agency coordinated with each other.

David Coleman Headley testified Monday at the trial of Chicago businessman Tahawwur Rana, who is accused of giving Headley cover when Headley scouted sites in Mumbai for the Pakistani militant group Lashkar-e-Taiba.

Headley’s testimony is being closely watched for what it might reveal about suspected links between Lashkar and Pakistan’s intelligence agency, which has been under scrutiny since Osama bin Laden was killed.

In their opening statement,prosecutors on Monday said Rana used his immigration business as a cover to help a co-conspirator scount potential terror targets in India.

LISTEN: Newsradio 780’s Nancy Harty Reports

U.S. Attorney Sarah Streicker said Rana’s First World Immigration business gave his convicted accomplice, Headley, a cover to allow him to travel to India and take photos of potential targets. Rana is charged as a conspirator in the 2008 terror attack in Mumbai, India.

Streicker said that Rana “is not charged with killing someone, not charged with picking up a gun or grenade, rather the charges stem from the support he provided.”

Prosecutors also told jurors that they would provide e-mails between Headley and Rana that would prove their conspiracy.

The trial goes deeper than just the charges against Rana, CBS 2’s Susanna Song reports.

It raises questions about Pakistan’s intelligence operation and its cooperation with the United States in fighting terror–especially against al Qaeda.

International relations experts say the trial could complicate the already fragile relationship between the U.S. and Pakistan.

Witnesses who take the stand could reveal Pakistan’s links to terrorism and how, if at all, it was involved in the Mumbai attacks.

Rana is accused of helping facilitate the 2008 rampage in Mumbai.

Prosecutors allege Rana provided cover for a former friend to scout sites in the attacks that killed more than 160 people, including six Americans.

He’s also accused of helping plot an attack that never took place on a Danish newspaper that printed cartoons of the prophet Mohammed.

Rana has pleaded not guilty.

If convicted Rana faces life in prison

Watch & Listen LIVE