Tamerlan Tsarnaev, a 26-year-old Chechen immigrant, also harbored an increasingly alarming hatred of his adopted country.

“He said in Russian, ‘I don’t like what America is doing,’ ” a Latvian neighbor told The Post yesterday, recalling a chat he had with the Boston bombing suspect, who was killed early yesterday in a shootout with police in Watertown, Mass.

“I said, ‘What do you mean?’ He said, ‘I don’t like it because they shouldn’t be in Muslim countries.'”

Tamerlan Tsarnaev was thrown out of the mosque — the Islamic Society of Boston Cultural Center — about three months ago, after he stood up and shouted at the imam during a Friday prayer service, they said. The imam had held up slain civil rights leader Martin Luther King Jr. as an example of a man to emulate, recalled one worshiper who would give his name only as Muhammad.

Enraged, Tamerlan stood up and began shouting, Muhammad said.

“You cannot mention this guy because he’s not a Muslim!” Muhammad recalled Tamerlan shouting, shocking others in attendance.

“He’s crazy to me,” Muhammad said. “He had an anger inside.… I can’t explain what was in his mind.”

The father of Tamerlan and Dzhokhar Tsarnaev, Anzor, told Channel 4 News that the elder brother had telephoned their mother a few days after the bombings…

Tamerlan told her the FBI had just rung him and accused him of being behind the attacks, and that he had responded by saying “that’s your problem”, Mr Tsarnaev claims…

If the claim is true, then it raises questions over the FBI handling of the investigation into the Boston bombings.

People will be asking about how the alleged telephone call may have fitted into the chain of events – from the attack itself up to the firefight that took place three days later, in which a police officer, as well as Tamerlan, was killed.

A police official source in Makhachkala, Dagestan, told NBC News on Sunday that the Russian internal security service reached out to the FBI last November with some questions about Tamerlan, and handed over a copy of case file on him.

Tsarnaev had first popped up on the local police radar in Dagestan last summer, the source said. During routine surveillance of an individual known to be involved in the militant Islamic underground movement, the police witnessed Tamerlan meet the latter at a Salafi mosque in Makhachkala, the police official said.

It was one of six times in total that surveillance officials witnessed Tsarnaev meeting this militant at the same mosque, according to the police official.

The militant contact later disappeared, the police official said, but so did Tsarnaev before investigators had a chance to speak with him. The FBI never responded, according to the Dagestani police official.

Rep. Michael McCaul (R-Texas) is asking why the FBI did not scrutinize Tamerlan Tsarnaev more closely when he returned from that six-month journey, which reportedly included a leg in Chechnya.

“I personally believe that this man received training when he was over there, and he radicalized from 2010 to the present,” McCaul said in an interview with Candy Crowley on CNN’s “State of the Union” program.

“One of the first things he does [upon his return] is puts up a YouTube website throwing out a lot of jihadist rhetoric. Clearly something happened, in my judgment, in that six-month timeframe – he radicalized at some point in time,” McCaul added. “Where was that and how did that happen?”…

“If he [the older brother] was on the radar and they let him go, if he was on the Russians’ radar, why wasn’t a flag put on him, some sort of customs flag?” McCaul asked.

The significance of the trip was magnified late Friday when the F.B.I. disclosed in a statement that in 2011 “a foreign government” — now acknowledged by officials to be Russia — asked for information about Tamerlan, “based on information that he was a follower of radical Islam and a strong believer, and that he had changed drastically since 2010 as he prepared to leave the United States for travel to the country’s region to join unspecified underground groups.”

The senior law enforcement official said the Russians feared he could be a risk, and “they had something on him and were concerned about him, and him traveling to their region.”

But the F.B.I. never followed up on Tamerlan once he returned, a senior law enforcement acknowledged on Saturday, adding that the bureau had not kept tabs on him until he was identified on Friday as the first suspect in the marathon bombing case…

As a routine part of his application, Tamerlan Tsarnaev was subject to a criminal-background check by the F.B.I. The authorities confirmed that he had been involved in a domestic violence incident while he was a resident with a green card, the officials said. A review of the episode delayed his citizenship application, the officials said, but it was not deemed serious enough to disqualify his application.

Intelligence sources tell CNN it is “rare” for Russians to reach out like that, to ask the FBI to look into someone as they did with Tsarnaev…

“There’s going to be a lot of questions, that’s one of them obviously,” said Rep. Michael Capuano, D-Massachusetts. “I’m sure the FBI is going to want to ask those questions of themselves, as well.”…

What is not known now is how many people the FBI interviewed, over what period of time, and whether there was any future surveillance. Also unknown is whether the Russian FSB gave the U.S. a list with many names on it, or just a few – whether it was a standard request, or something more unique that should have warranted more attention.

“These are two relatively young men who don’t seem to have the ability to finance what I see going on,” Lynch said in an interview. “They seem to be very well supplied. How do these type of individuals like that get the training and resources to conduct an operation like this?”…

Lynch, a Democrat who is running in the special election for a Senate seat, said investigators are also scrambling to learn more from the Russian government about why Tamerlan Tsarnaev gave them concern in 2011.

“What was the source of their inquiry? What suspicions drove that? It might have been his associations with individuals there. Were [Russian authorities] forthcoming with the FBI?”

Lynch added that he believes Congress must ultimately play a role in getting more answers and determining if the attack could have been stopped.

BROKAW: I think there’s something else that goes beyond the event that we’ve all been riveted by in the last week. We have to work a lot harder at the motivation here. What prompts a young man to come to this country and still feel alienated from it, to go back to Russia and do whatever he did? I don’t think we’ve examined that enough. There was 24/7 coverage on television, a lot of newspaper print and so on, but we have to look at the roots of all this because it exists across the whole subcontinent, in the Islamic world. I think we also need to examine the use of drones, which the United States is involved in. There are a lot of civilians who are innocently killed in Pakistan, Afghanistan, and in Iraq. And I can tell you having spent a lot of time over there; young people will come up to me on the streets and say, “We love America. If you harm one hair on the head of my sister, I will fight you forever.” And there is this enormous rage against the what they see in that part of the world as the presumptuousness of the United States.

“This is not a one-off. This was a glimpse of the future,” he continued. “This is granular terrorism that one, two, three people can carry out. We live in a world where power is diffused, where individuals are, in turn, empowered.”

“There’s ample evidence to suggest this man was a radical Islamist and that he and his brother had ties to overseas organizations,” Graham told Candy Crowley on CNN’s “State of the Union” program. “We should reserve the right, after the public-safety exception expires, to look at him as an enemy combatant, continue to collect evidence, and if we find evidence, go to him … without a lawyer present to gather intelligence.”

Disagreeing with Graham, Sen. Charles Schumer (D-N.Y) said law enforcers can get all the information they need from Tsarnaev without designating him an enemy combatant – a move that would only complicate the investigation with a thorny legal debate, Schumer warned.

“We don’t need ‘enemy combatant’ to get all the information we need out of him,” Schumer told Crowley. “We don’t have to cross the line and say he should be an enemy combatant, which could be challenged in court.”