By Evan Kohlmann, NBC News Terrorism Analyst

The sole surviving terrorist of the Mumbai attacks allegedly spent 18 months training at camps run by Lashkar-e-Taiba (LET), a banned Pakistani militant organization with a long history of high-profile attacks in India and Indian-controlled Kashmir. And, as NBC News has reported, Indian authorities also have found the names of several high-ranking LET members in the satellite phone used by one of the Mumbai perpetrators.

So what is Lashkar-e-Taiba, and was the group truly behind the horrific attacks in Mumbai’s hotels, train station and restaurants? Lashkar’s political wing offered reporters in Pakistan a rare tour of their sprawling, 200-acre headquarters today, and allowed me to interview one of their top officials yesterday. In a phone interview, the LET’s Abdullah Muntazir repeatedly denied any involvement in the attacks. “No, not at all,” said Muntazir, a chief spokesman of LET’s accused political wing, Jamat-ud-Dawa.

“The violence against the general public carried out by any individual, group, or any government--whether it is committed in Mumbai, or in Kashmir, Afghanistan, or in Iraq--that cannot be justified at any cost. And Islam does not allow its followers to kill innocent people, to target public places,” Muntazir said. “Blowing up [bombs] in public places… from my point of view, that we cannot endorse and we have no relation to such kind of things.” 

During the press tour today at the group’s headquarters outside Lahore, Muntazir continued with his denials. “We are a charity organization and these premises are just an educational and medical complex,” he said. “We condemn India for putting [our leader’s] name on the list of terrorists… India is blaming us because its their habit and the moment the attacks happened in Mumbai, they started blaming us without any proof or evidence,” Muntazir told reporters today.

By Jim Popkin, NBC News Senior Investigative Producer

The Department of Homeland Security and the FBI today briefed building owners in the United States "regarding the tactics terrorists used in the attacks last week in Mumbai, India." The five-page "Intelligence and Analysis Note" said that the DHS and FBI "have no credible or specific information that terrorists are planning operations against public buildings in the United States." But it is important for building owners and operators "to be aware of potential attack tactics," the note said.

The DHS and FBI gathered details of the attack from open reports and "interrogations of a captured terrorist," the note said.  It ticked off many of the now well-reported details, including the use of boats to gain unfettered access to Mumbai and the "synchronized and coordinated" nature of the massacre.

But it also included some lesser known facts about the terrorist assault. The note said, for example, that the "attack planners used publicly available commercial imagery to plan the attack," such as satellite mapping of Mumbai. It added that while "at least 10 operatives" circumvented security by entering Mumbai from the sea, "others arrived in the city as many as four days prior to the attack."

The note said that the terrorists "were clean shaven and dressed in Western street clothing, possibly to blend in with the population" and that they entered the Taj Mahal Hotel through back alleys to surprise security guards. Once inside, they "moved continuously throughout the facilities." The constant movement "made it difficult for authorities to identify locations of attackers and hostages," the FBI and DHS wrote.

By Robert Windrem and Aram Roston, NBC News

Some U.S. and Indian counter-terrorism officials are asking if India’s most notorious reputed mobster -- thought to run a worldwide crime ring -- had a hand in the slaughter that devastated Mumbai last week.

His name is Dawood Ibrahim, a flashy gangster with alleged ties to contract hits, narcotics, gambling and even the film industry. Even more significantly, though, may be his alleged ties to al-Qaida and the terrorist group that's leading the list of suspects.

Ibrahim's international crime ring has been dubbed the "D-Gang" by the Indian press. In Mumbai, police have said for years that political and religious terrorism have been interwoven with crimes such as drugs, prostitution, gambling and contract hits. Indian newspapers ascribe legendary feats of criminality to the group.

Marie-Lou Fernandes was a Mumbai Deputy Police Commissioner until 2005, and tells NBC News that Dawood Ibrahim may not have been the instigator, but must have helped.

Although there's no evidence he was involved, Fernandes said," It appears to me there is only one person who could orchestrate that: Dawood Ibrahim. Everything is pointing to Dawood Ibrahim. He has the expertise and the resources."

Fernandes says she knew many of the officers killed in the attacks and lauds their performance. She said that Ibrahim is a likely participant. "Only an operative like Dawood would have been able to carry it out," Fernandes repeated.

Ibrahim, called a "crime lord" by the U.S. government, has been a fugitive for well over a decade. He was accused of orchestrating the 1993 bombings in Mumbai, which killed more than 250 people. In that case, munitions for the attack were allegedly infiltrated into the city after they were brought in by boat to the coast by Dawood Ibrahim's men. There have been numerous criminal convictions in the case. Ibrahim was charged, but never brought to trial, because police could never catch him.

By Jim Popkin, NBC News Senior Investigative Producer

In a password-protected document, officials connected to the State Department report that some of the Mumbai terrorists reportedly were trained by the Lashkar-e-Tayyiba terrorist group, with "camps located in Mansera and Muzzarafabad in Pakistani-administered Kashmir." The 10 terrorists behind the Mumbai massacre "spoke Punjabi" and were of "likely Pakistani origin," the report said.

The 17-page report was written by the Overseas Security Advisory Council, a public-private group that serves as the liaison between the State Department and multi-national corporations. The report is not an official State Department document, and says it uses both "embassy reporting" and press accounts to substantiate its analysis of the deadly attacks.

NBC News obtained a copy of the PowerPoint presentation, which is distributed in password-protected form to clients of OSAC. On its website, OSAC describes itself as "a Federal Advisory Committee with a U.S. Government Charter to promote security cooperation between American business and private sector interests worldwide and the U.S. Department of State."