U.S. and Pakistani investigators are pursuing a new lead in the failed Times Square bombing: That a major in Pakistan’s army knew of Faisal Shahzad’s plans to attack U.S. targets months before Shahzad tried to ignite a car bomb in the heart of New York City.

Investigators believe the major, who is suspected of having ties to the Pakistani Taliban, did not tell Pakistani authorities about preparations for an attack and may even have aided the plotters, officials said Thursday.

Pakistani authorities arrested the military officer this week, officials said. U.S. investigators have been told by Pakistani officials that the major learned of Shahzad's plans from another suspect who is accused of funding the operation, according to a senior U.S. anti-terror official.

The major has since resigned from the military, said the official, who requested anonymity because the case remains open.

"We are being told the major was aware of the plot," the senior anti-terror official said. "We don't know yet how much of a role he had, if any. He did have connections to the Pakistani Taliban."

U.S. investigators have been given only sketchy details about the major and his arrest, which was first reported Wednesday by the Los Angeles Times. A spokesman at the Pakistani embassy in Washington said Thursday that embassy officials had heard reports of this week's arrest in Pakistan, but had not been able to confirm them or obtain details.

In recent days, U.S. officials have given ProPublica a clearer account of Shahzad's dealings with the Pakistani Taliban. According to the evidence gathered so far, officials said, the Pakistani militants financed and supported the plot but did not direct Shahzad's choice of targets or other specifics.

The officials said the 30-year-old appears to have received limited training from the Pakistani Taliban in North Waziristan. Then the militants sent him to Karachi to collect $17,000 from the money man who is an associate of the former major, the senior official said.

Allegations about the major, if confirmed, would deepen U.S. concerns about the role of the Pakistani military and intelligence in the fight against terrorism. Figures linked to the Pakistani armed forces and intelligence agencies have surfaced in previous terror cases, especially those involving Punjab-based extremist groups that target India and have a history of ties to the security forces. In January, federal prosecutors in Chicago indicted a retired Pakistani major who allegedly worked with a Pakistani-American businessman and al-Qaida operatives in a plot against the Danish newspaper that published the caricatures of the prophet Mohamed in 2005.

The potential involvement of a military man in an attack against New York City would set a troubling precedent. The news of the arrest comes during a visit to Pakistan by National Security Advisor James Jones and CIA director Leon Panetta. The U.S. officials were in Pakistan to discuss stepping up cooperation in the Times Square investigation, and the larger battle against al-Qaida and its allies, with Pakistani leaders.

After the failed May 1 attack in Times Square, FBI agents arrested Shahzad, a naturalized U.S. citizen, aboard a flight as it was about to take off for Dubai. The 30-year-old has spent days talking to investigators, describing his training in Pakistan and providing leads about his contact with the Pakistani Taliban, U.S. officials say.

Attorney General Eric Holder and other officials have said the Pakistani Taliban financed, facilitated and helped direct Shahzad's attempted attack. But anti-terror officials said the unfolding investigation paints a more nuanced picture and provided new details in conversations this week.

Although elements of the Pakistani Taliban were eager to support Shahzad, administration officials said the organization did not exert command and control over the plot. Taliban militants didn't choose the target or time, and Shahzad wasn't recruited for an operation. Instead, he went to Pakistan in search of support with help from two former roommates who are now in custody in Pakistan.

The Pakistani Taliban allowed Shahzad to spend time with fighters, but he was not taught how to build a car bomb or how to execute an operation of the magnitude he was planning, officials said. That may help explain the mistakes that authorities say he made building the propane-based bomb that failed to ignite in Times Square.

President Obama's counterterrorism adviser, John Brennan, said Shahzad is the latest in a series of American terror suspects who they believe got training and support from militant networks overseas.

"They took advantage of their U.S. personage and their U.S citizenship and were operating in many respects not necessarily alone, but in manners that made it more difficult for us to detect," Brennan said during a policy dinner Tuesday sponsored by The Nixon Center. He added: "These are the ones I am concerned about."

The intelligence community is poring over thousands of e-mails Shahzad sent to friends and associates in Pakistan. Some communications allude to his desire to carry out an attack. Many of his claims are being corroborated through suspects in custody in Pakistan who are also cooperating, according to an official familiar with the investigation.

It was Shahzad's statements to investigators that led to the arrest of the former major in Pakistan.

The chain of events began when Shazhad identified a suspect named Shuab, also known as Iqbal, as an associate of the Pakistani Taliban who ran a hawala, or informal money transfer operation, in Karachi. After the American trained in North Waziristan last summer, Taliban militants sent him to Karachi to obtain funds from Shuab for his planned attack, according to the senior anti-terror official. The money man provided Shazhad with $17,000. The Pakistani-American returned early this year to the United States, where militants eventually sent him another $34,000, officials said.

Acting on the U.S. lead, Pakistani investigators arrested the alleged financier about a week ago. He then revealed that he had discussed Shahzad's terrorist plans with the major, who is believed to be a sympathizer and fellow associate of Taliban militants, according to the senior official. The major resigned from the military in the past several months, but the reasons and circumstances for that move are not known, the senior official said.

At the time, Shahzad may not have decided on Times Square as a final target, but investigators believe the major and the other Pakistani suspects knew he was planning to strike in the New York area, the official said.

Shahzad "knew he was going to do a car-bombing," the official said. "He said he considered a number of targets: Times Square, a nuclear facility in Connecticut, Rockefeller Center, the financial district."

It is not yet clear whether Shahzad and the major had any direct contact, the senior official said. The former military man was arrested not by the ISI, Pakistan's most powerful spy agency, but by a military intelligence service. While the ISI has played a central role in the Times Square investigation and in other major terror cases, the spy service and other branches of the security forces have also periodically been accused of colluding with Islamic extremists.