Pakistani-American terrorist David Headley’s plea bargain under which he confessed to plotting the Mumbai attacks throws light on close links between al-Qaeda and LeT, according to former CIA expert Bruce Riedel.

The 49-year-old Headley’s story showed clear contours of the close relationship between al-Qaeda and the Pakistani militant group Lashkar-e-Taiba, Riedel, who led the review of the Obama Administration’s AfPak strategy, was quoted as saying by The New York Times.

Revelations in Headley’s plea agreement around al-Qaeda’s European cell were particularly disturbing, said Mr. Riedel, who was also a member of the National Security Council in the Clinton administration and is now at the Brookings Institution.

They showed that “al-Qaeda still has a significant operational infrastructure somewhere in Europe,” he said.

The paper said the plea agreement released last week showed that Headley moved effortlessly between the U.S., Pakistan and India for nearly seven years, training at a militant camp in Pakistan on five occasions.

Headley’s travels included several cities in India, meeting with a senior operative of al-Qaeda in Pakistan’s tribal belt and two trips to North Waziristan region, it said.

“These and other new details of Headley’s activities, contained in the plea agreement, raise troubling questions about how an American citizen could travel for so long undetected from his home base in Chicago to well-established terrorist training camps in Pakistan,” the Times said.

It was from here that Headley planned the Mumbai attacks and got in touch with an al-Qaeda cell in Europe that may still be operative, the report said.

“The (plea agreement) document shows the cell was well supplied with weapons and money and primed for an attack until the moment Headley was arrested by the FBI at O’Hare airport last October,” the daily wrote.

As Headley became “more intensely involved in the web of militant activities in Pakistan — sometimes training for months at a time — and then making five trips to Mumbai from 2006 to 2008 to scout locations,” he kept his base in Chicago, it said.

In his plea, Headley said that LeT remained active behind the veil of a public charity, an apparent reference to JuD, and continued to be aided by ex-Pakistani military officials.

The plea agreement showed that a retired Pakistani military officer, Col. Abdur Rehman Hashim Syed, known as Pasha, was Headley’s main contact with LeT. In early 2009, Syed introduced Headley to Muhammad Ilyas Kashmiri, an al-Qaeda operative in North Waziristan and then Syed served as a go-between, the paper reported.