(Wikimedia Commons)

The Washington Post reported that the 19-year-old suspect admitted to planting the explosives near the marathon finish line on April 15, which killed three people and wounded more than 250 others.  Tsarnaev has also alluded that his brother Tamerlan, 26, who died Friday after a firefight with police in Watertown, was the driving force behind the plan.

Boston public health officials are now reporting that 264 people needed treatment at hospitals for injuries incurred from last week’s marathon bombings, almost 100 more than reported. Authorities had said that about 180 people were inured, but those were just the victims brought to the hospitals in the immediate aftermath of the April1 15 explosions, WTOP in Boston reported.

City officials  allowed the first business people and residents back into the Boylston Street crime scene area Tuesday more than a week after the first explosions at the Boston marathon finish line. Employees told the Boston Globe that the scene was "surreal" as they worked to clean up trash, spoiled food and collect belongings. Access to the area is still limited.

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Evidence suggests that the two brothers were not connected to, or directed by, any foreign terrorist organization. Instead, officials believe the brothers were “self-radicalized” through Internet sites and U.S. involvement in the Muslim world.

Anonymous officials told the Associated Press that Tamerlan Tsarnaev read jihadist websites, propaganda and magazines, including Inspire, an English-language online publication produced by al Qaeda’s Yemen affiliate. The 26-year-old also frequently attended prayer services at the Islamic Society of Boston mosque in Cambridge.

Dzhokhar Tsarnaev communicated to authorities that he and his brother acted alone, and that they were also motivated by religion. U.S. officials are still trying to piece together a motive, as well as a detailed timeline of a trip the older Tsarnaev took to Russia last year, though no evidence suggests he received instructions on how to carry out the attack.

“These are persons operating inside the United States without a nexus” to an overseas group, a U.S. intelligence official said.

ALSO: Boston Bombing Suspect Says He And Brother Acted Alone

From the Washington Post:

"U.S. officials have said that the FBI questioned Tamerlan Tsarnaev at the behest of Russian authorities who had become concerned that he was becoming radicalized. The request was conveyed to officials at the U.S. Embassy in Moscow. U.S. officials said they sought follow-up information from Russia, but that Moscow failed to respond."

The L.A. Times reported that an unnamed government had contacted the FBI, warning of the 26-year-old’s drastic changes since 2010 and that he was preparing to leave the U.S. to “to join unspecified underground groups,” according to an official statement from the FBI.

U.S. officials have not named the foreign nation, but it is presumed to be Russia.

Authorities in Massachusetts are also investigating whether Tamerlan may have killed his best friend in a triple homicide that occurred in Waltham, Mass., in September 2011.

Dzhokhar Tsarnaev was charged in his hospital bed Monday with using a weapon of mass destruction to kill, and could face the death penalty if convicted.

Though he cannot speak due to gunshot wounds to his throat, Dzhokhar has been cooperatively communicating with authorities as they continue to connect all the pieces behind the attacks rattled Boston last week and is now being called the first successful terrorist attack since 9/11.

Read the whole story at The Washington Post.

Read more of Neon Tommy's coverage on the Boston Bombings.

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