MEDFORD, Mass. -- She was remembered for her smile.Outside St. Joseph Catholic Church, Krystle Campbell's second-grade teacher reached into her purse Monday and pulled out a class picture from April 1991 -- 21 sweet, gawky children, and Krystle in the back row "with the biggest smile," Margaret Regan said as she waited for her former student's funeral to begin.Inside, the Rev. Chip Hines told Campbell's friends and family that "every picture I have ever seen" of the 29-year-old who died a week ago at the Boston Marathon "has had that ever-present smile.""Let these words from her parents be what you remember about Krystle," Hines said, during the first of four services expected this week stemming from the spree of violence. "Unselfish ... Always smiling."A week after the destruction began near the finish line of this country's most historic marathon, the greater Boston region began to move on.Boylston Street -- where the pressure-cooker bombs were set off -- was officially released by the FBI, handed back to the city. It is expected to reopen to traffic in coming days. Taps sounded. An American flag that flew over the boulevard-turned-crime-scene was lowered, folded and handed to Mayor Thomas M. Menino.At 2:50 p.m. EDT, exactly a week after the first explosion, a moment of silence was observed -- in Paris, where runners stopped to remember the three who died and more than 200 who were wounded. In Los Angeles, where Mayor Antonio Villaraigosa interrupted a news conference on "Formula E" racing.At the White House, where President Barack Obama paused, and the New York Stock Exchange, where trading halted. On the floor of the U.S. Senate, where legislators were debating Internet taxation.And all around this stunned region, where residents will struggle to get their lives back for months to come.Near the finish line, the "moment" of silence lasted for 10 minutes. The crowd began to form well before 2:50 p.m. and swelled to several hundred people. Attendees filled the intersection at Boylston and Berkeley streets and snaked around corners. Workers in nearby office buildings peered from above.All eyes were on the empty blocks still cordoned off since the attacks. Heads bowed. Tears fell. Lips moved in silent prayer. A Boston EMS vehicle pulled up, lights flashing. The driver got out near the barricades and stood at attention.At around 3 p.m., he raised his arms over his head, triumphant. The crowd cheered.Patti Handloss, a retired Episcopal priest, said she had returned to the area the day after the attacks to have dinner and send a message: "We're not afraid. We're not going to let terrorism chase us out of our city. And as a Christian, it was important to say, not only are we not going to let them chase us away, we're going to stand in love."On the steps of the 215-year-old Massachusetts State House, its golden dome overlooking downtown Boston, first there was silence, then music.On Monday evening, 23-year-old Lu Lingzhi was memorialized in a packed ballroom at Boston University, where she was a graduate student. She died far from her family in China, far from her home, far from her beloved dog, said classmate Zheng Minhui.Before she died, Lingzhi was learning to live off-campus, said her roommate, Jing Li. Yes, she often burned breakfast and set off the fire alarm, but the two young women would also sing out loud while walking down Boston's busy streets.Funeral plans have yet to be solidified for 8-year-old Martin Richard. On Wednesday, Vice President Joe Biden will attend a memorial at the Massachusetts Institute of Technology for the fourth victim, Sean Collier, a campus policeman who was shot to death after confronting the suspects during last week's manhunt.Developments in the investigation continued to pour out Monday.The two brothers suspected of bombing the Boston Marathon appear to have been motivated by a radical brand of Islam but do not seem connected to any Muslim terrorist groups, U.S. officials said Monday after interrogating and charging Dzhokhar Tsarnaev with crimes that could bring the death penalty.Tsarnaev, 19, was charged in his hospital room, where he was in serious condition with a gunshot wound in the throat and other injuries suffered during his attempted getaway. His older brother, Tamerlan, 26, died Friday after a fierce gunbattle with police.The Massachusetts college student was charged with using and conspiring to use a weapon of mass destruction. He was accused of joining with his brother in setting off the shrapnel-packed pressure-cooker bombs that killed three people and wounded more than 200 a week ago.The brothers, ethnic Chechens from Russia who had been living in the U.S. for about a decade, practiced Islam.Two U.S. officials said preliminary evidence from the younger man's interrogation suggests the brothers were motivated by religious extremism but were apparently not involved with Islamic terrorist organizations.Dzhokhar communicated with his interrogators in writing, precluding the type of back-and-forth exchanges often crucial to establishing key facts, said the officials, who spoke on condition of anonymity because they were not authorized to discuss the investigation publicly.They cautioned that they were still trying to verify what they were told by Tsarnaev and were looking at such things as his telephone and online communications and his associations with others.In the criminal complaint outlining the allegations, investigators said Tsarnaev and his brother each placed a knapsack containing a bomb in the crowd near the finish line of the 26.2-mile race.Additional arrestsAlso on Monday, Kazakhstan's Ministry of Foreign Affairs issued a statement saying two foreign nationals arrested Saturday in the Boston area on immigration violations are from Kazakhstan and may have known the two marathon bombing suspects.The foreign ministry said U.S. authorities came across them while searching for "possible links and contacts" to Dzhokhar Tsarnaev.Officials have not disclosed the names of the nationals, who the ministry said were found to have "violated the U.S. visa regime."The country's consul is in Boston to work with the students and their families, the statement said.The ministry Monday reaffirmed its cooperation with the U.S. on terrorism and emphasized that it "strongly condemns terrorism" in any form.Amid disclosures that Russia tipped the FBI in 2011 that one of the Boston Marathon bombers had become a Muslim radical, Republican leaders of the House Homeland Security Committee plan to hold hearings to examine what the bureau and U.S. intelligence agencies might have done to thwart last week's attack.The committee's chairman, Texas Rep. Michael McCaul, and New York Rep. Peter King, a key subcommittee chairman, asserted that the elder of the two Chechen brothers implicated in the Boston attacks appeared to be the fifth person since 9-ll "to participate in terror attacks" after being interviewed by the FBI.In a letter over the weekend, they demanded "all information possessed by the U.S. government" in advance of the bombings relating to Tamerlan Tsarnaev, the elder brother who died in a police shootout early Saturday.Amid a swirl of emotions in Boston, there was cause for some celebration: Doctors announced that everyone injured in the blasts who made it to a hospital alive now seems likely to survive.That includes several people who arrived with legs attached by just a little skin, a 3-year-old boy with a head wound and bleeding on the brain, and a little girl riddled with nails."All I feel is joy," said Dr. George Velmahos, chief of trauma surgery at Massachusetts General Hospital, referring to his hospital's 31 blast patients. "Whoever came in alive stayed alive."This report includes material from the Los Angeles Times, The Associated Press and McClatchy Newspapers.