WASHINGTON (Reuters) - The senior Republican on the U.S. Senate Intelligence Committee cast doubt on Tuesday on the Obama administration’s assertions that the Pakistani Taliban orchestrated the attempted car bombing in New York on May 1.

Senator Kit Bond, after a briefing by U.S. counterterrorism and law enforcement officials, said it was not confirmed the accused bomber -- Faisal Shahzad, a naturalized U.S. citizen from Pakistan -- was working for the Islamist group.

U.S. Attorney General Eric Holder said on Sunday evidence showed the Tehrik-e-Taliban Pakistan (TTP) helped direct the failed attack in New York’s teeming Times Square and likely assisted in financing it.

“I am not convinced by the information that I’ve seen so far that there was adequate, confirmable intelligence to corroborate the statements that were made on Sunday television shows,” Bond told reporters after the classified briefing.

“We’ve heard lots of suspicions and tenuous connections, but as far as I’m concerned you can’t make statements prior to getting the intelligence.”

Republicans have been openly and repeatedly critical of the handling of terrorism cases by the administration of President Barack Obama, a Democrat.

The chairwoman of the Senate Intelligence Committee, Dianne Feinstein, emerged from the same briefing disagreeing with Bond. She said there was a “high likelihood” of interactions between Shahzad and the Pakistani Taliban.

TTP, based in Pakistan’s lawless border regions, claimed responsibility on May 2 for the attempted attack.

Shahzad, 30, was arrested trying to flee the United States on a flight to Dubai. He has admitted to the plot and to receiving bomb training in Waziristan, Pakistan, U.S. prosecutors have said.

One U.S. official, speaking on condition of anonymity, said later on Tuesday: “There are indications that the TTP was involved in the Times Square attempt.” A Justice Department spokeswoman declined to comment on Bond’s remarks.

As part of the U.S.-led war against Islamist militants in neighboring Afghanistan, U.S. drone aircraft launched two attacks on a Taliban and al Qaeda stronghold in Pakistan, killing at least 24 suspected fighters.

“COMPLETELY UNDER THE RADAR”

U.S. officials initially doubted the TTP claim over the New York plot. But after Shahzad’s arrest, Holder came out publicly to say there was a connection.

“The evidence we’ve now developed shows that the Pakistani Taliban has directed this plot,” Holder said on NBC’s “Meet the Press” on Sunday. “And I suspect that we are going to come up with evidence which shows that they helped to finance it.”

Feinstein expressed concern that Shahzad was “completely under the radar” of law enforcement.

“It’s clear we’re facing a new kind of attacker, who’s already here and able to hide in plain sight, and we need to think about new defenses,” she said.

Under pressure from Democrats in the Senate, the State Department said on Tuesday it was looking at adding TTP to the U.S. list of “foreign terrorist” groups.

In New York, the city’s police commissioner Ray Kelly told reporters Shahzad knew authorities were pursuing him and tried to leave the country after federal officials leaked information about the investigation.

Shahzad was arrested by U.S. Customs and Border Protection agents in New York minutes before his Emirates Airline flight was to depart. He had eluded law enforcement agents earlier in the day.

Kelly said Shahzad was tipped off by media reports that authorities were hunting for a Pakistani-American identified as the buyer of the sport utility vehicle used to carry a crude bomb made of fuel and fireworks into Times Square.

“There was an inordinate amount of information given out by somebody in this case,” Kelly said. “He already knew that we were looking for him. That is not helpful and I think the government has to look internally to see that doesn’t happen.”

Kelly said the information was not leaked by New York police. The FBI and Justice Department declined to comment.

Since his arrest, Shahzad has been talking with authorities and waived his legal rights.

“Over the past week-and-a-half we have been working to understand everything we can about Shahzad,” Kelly said, adding his story was “another classic case of homegrown terrorism.”

At an appearance in Oakland, California, Holder told reporters the incident was “troubling but also indicative of what we’ve seen over the past year.”