Boston blasts site reopens as officials try to question suspects' parents

(CNN) -- Nine days after terrorists turned Boylston Street into a gruesome scene of carnage, the city of Boston is taking it back.

Workers replaced missing bricks and patched up concrete just before opening the area to pedestrian traffic Wednesday morning. It's another sign that Boston is recovering from the dual bombings that killed three and wounded hundreds more.

But the impact of the blasts is far from over.

On Wednesday, mourners will gather at the Massachusetts Institute of Technology to honor campus Officer Sean Collier, who authorities say was fatally shot by the suspected bombers last week.

And as more details slowly emerged from the bedridden suspect, U.S. officials arrived in Dagestan to try to interview the parents of the suspected bombers.

Suspects received welfare

The two suspects, Tamerlan and Dzhokhar Tsarnaev, received welfare benefits when they were growing up. And Tamerlan received them for his family through 2012, the Massachusetts government says.

"The brothers were not receiving transitional assistance benefits at the time of the incident and have not received any transitional assistance benefits this year," the Department of Health and Human Services emphasized.

"The Tsarnaevs' parents are former recipients of transitional assistance benefits, and both Dzhokhar and Tamerlan Tsarnaev received benefits through their parents when they were younger. Separately, Tamerlan and his family received benefits until 2012, when the family became ineligible based on their income."

Tamerlan, 26, who died after a shootout with police, was married and had a young daughter.

Dzhokhar, 19, has indicated that his older brother masterminded the bombing, according to a U.S. government source.

Hunting for clues abroad

A delegation from the U.S. Embassy in Moscow arrived in Dagestan as part of the investigation into the Boston Marathon bombings, an embassy official told CNN's Phil Black on Wednesday.

The Russian government is cooperating with the trip and with FBI in its investigation, the source added.

Kheda Saratova, a human rights activist in Dagestan, told CNN that U.S. and Russian investigators talked with the brothers' parents Wednesday and the "conversation" is over. She got that information from the brothers' mother.

The Tsarnaev family hails from the Russian republic of Chechnya and fled the brutal wars there in the 1990s. The two brothers were born in Kyrgyzstan, and their parents live in Dagestan.

U.S. Secretary of State John Kerry said he suspects the older brother may have been influenced during his trip to Russia.

"We just had a young person who went to Russia, Chechnya, who blew people up in Boston," Kerry said Wednesday during a trip to Belgium. "So he didn't (say) where he went, but he learned something where he went, and he came back with a willingness to kill people."

A senior State Department official later clarified that Kerry "was simply expressing broad concern about radicalism rather than indicating any new information or conclusion about the individuals involved."

Meanwhile, Dzhokhar Tsarnaev, the surviving suspect, has cited the U.S. wars in Afghanistan and Iraq as motivating factors behind the attack, a U.S. government official said Tuesday.

The younger brother remains hospitalized with an array of gunshot wounds, but has been upgraded from serious to fair condition.

He has been communicating with investigators in a limited fashion from his hospital bed and told them that neither he nor his brother Tamerlan had any contact with terrorist groups overseas. But the official cautioned that the interviews were preliminary and that Tsarnaev's account needs to be checked out.

The 19-year-old also told investigators the brothers were self-radicalized via the Internet. Authorities are looking into whether the online English-language magazine Inspire, put out by Al Qaeda in the Arabian Peninsula, was used for instruction on how to make the bombs, but another source cautioned that other outlets could have provided that information.

Suspect shopped at fireworks store

More than two months before the marathon bombings, Tamerlan Tsarnaev bought two reloadable mortar-style fireworks from a New Hampshire store.

On February 6, he had one question for a store assistant at Phantom Fireworks in Seabrook, New Hampshire: "What's the biggest and loudest thing you have?"

After that, store Vice President William Weimer said, Tsarnaev shelled out $200 in cash for two "lock and load kits."

Weimer said such behavior is very common at the store. He said the store notified the FBI after discovering that the marathon bombing suspect had bought explosives there.

Law enforcement officials told CNN earlier Tuesday that the number of fireworks bought at the store was not enough to set off explosions the size of those at the Boston Marathon.

"My assumption is they bought this, experimented with it and decided against it and moved on and found another source," Weimer said.

Suspects' relatives 'devastated' by bombings

In a statement issued through their lawyers Tuesday, the suspects' sisters, Ailina and Bella Tsarnaev, said they were saddened "to see so many innocent people hurt after such a callous act."

"As a family, we are absolutely devastated by the sense of loss and sorrow this has caused," they said. "We don't have any answers but we look forward to a thorough investigation and hope to learn more."

And Tamerlan Tsarnaev's widow, Katherine Russell, issued a statement through her attorney's office saying she is "doing everything she can to assist with the investigation" and said she and her family are shocked and devastated.

The suspects' mother, Zubeidat Tsarnaev, said she thinks her sons were framed.

Speaking from her home in Dagestan, the mother said she thinks her sons were targeted "just because they were Muslim."

When asked whether she thinks her younger son will get a fair trial, she replied, "Only Allah will know."

CNN's Josh Levs, Jake Tapper, Julia Talanova, Carol Cratty, Brian Vitagliano, Laura Ly, Deborah Feyerick, Nick Paton Walsh, Julian Cummings, Barbara Starr, Susan Candiotti, Jessica Yellin and Joe Johns contributed to this report.