The Boston Marathon bombing suspects may have been headed to Manhattan to “party” after the attack that killed three people and wounded more than 260 others, New York City Police Commissioner Ray Kelly said.

Surviving bombing suspect Dzhokhar Tsarnaev told investigators that he and his alleged accomplice brother, Tamerlan Tsarnaev, were en route to the city Thursday night last week, Kelly told reporters Wednesday, NBC 4 New York reported.

Dzhokhar Tsarnaev, who was captured hiding in a tarp-covered boat in a suburban Boston backyard on Friday, could face the death penalty if convicted on terrorism charges. His older brother Tamerlan Tsarnaev, 26, died earlier Friday morning after authorities said the brothers hurled explosives during a firefight with police.

Kelly said that investigators believe, based on interviews with the younger brother, that the pair weren't coming to New York City for additional attacks, and were coming to celebrate, NBC 4 New York reported. Police said there was no threat to New York.

The development came as Boylston Street — the site of last Monday's twin explosions near the finish line of the Boston Marathon — reopened for the first time, while Vice President Joe Biden joined thousands for a memorial at MIT to honor a campus police officer authorities said was killed by the marathon bombing suspects.

Pedestrians snapped photos on Boylston, where orange construction cones surrounded fresh cement at the site of the first bombing, NBC News reported.

"The people of Boston are strong like cement. Strong people. They get together when it's needed," said Robert Bibias, a city masonry worker who helped cement over the crime scene. "I'm proud, but in the meantime, I'm sad."

The Copley subway station that had been closed since the bombings also reopened Wednesday, while the main branch of the Boston Public Library was set to reopen later in the day. Some stores directly affected by the blasts were still boarded up.

More 4,000 mourners, meanwhile, attended a public memorial service Wednesday for Sean Collier, the 26-year-old MIT campus officer. Vice President Joe Biden, speaking to Collier's parents, said, "My heart goes out to you. I hope you find some solace in what's being said here about your son."

He condemned the bombing suspects as "two twisted, perverted, cowardly, knockoff jihadis."

As Boston remembered one of its victims, suspect Dzhokhar Tsarnaev remained hospitalized at Beth Israel Deaconess Medical Center in fair condition. If his condition continues to improve, he will be moved to a high-security jail while awaiting a trial that could be two years away, experts told NBC News.

"As soon as he is medically cleared, he'll be moved," said Steven Swensen, a former U.S. marshal who now runs a judicial security consulting firm. "This is a high-threat, high-profile situation."

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In other developments:

— The Tsarnaev brothers' aunt said Wednesday that U.S. authorities told the family they could have Tamerlan's body, NBC News reported. Patimat Suleimanov also said a Boston mosque the family attended rebuffed a request by one of the suspects' uncles for a burial and funeral service.

— A spokesman for the state Office of Health and Human Services confirmed a Boston Herald report that Tamerlan Tsarnaev, his wife and their toddler daughter, had received benefits. The state said Tsarnaev and his brother Dzhokhar received welfare benefits as children through their parents while the family lived in Massachusetts. Neither was receiving benefits at the time of the bombing.

— Phantom Fireworks of Seabrook, N.H., said Tamerlan Tsarnaev bought 48 mortar shells at the store in February. Company Vice President William Weimer, however, said the amount of gunpowder that could be extracted from the fireworks would not have been enough for the Boston bombs.

— A lawyer for Tamerlan Tsarnaev's wife, Katherine Tsarnaeva, said his client "is doing everything she can to assist with the investigation," although he would not say whether she had spoken with federal authorities. Another lawyer for Tsarnaeva said the 24-year-old deeply mourned the loss of innocent victims in the bombings.

— The Massachusetts state House turned aside a bid by several lawmakers to reinstate the death penalty in certain cases, including the murder of police officers. In a 119-38 vote, the House sent the proposal to a study committee rather than advance it to an up-or-down vote.

— In New Jersey, the sisters of the suspects, Ailina and Bella Tsarnaeva, issued a statement saying they were saddened to "see so many innocent people hurt after such a callous act." Later, in brief remarks to several news outlets, Ailina described her elder brother as a "kind and loving man." She said of both brothers: "I have no idea what got into them" and also that "at the end of the day no one knows the truth."

— A fund created to benefit the victims of the Boston Marathon attacks has generated $20 million. Mayor Thomas Menino said more than 50,000 donors from across the world have made donations to One Fund Boston.

— Martin Richard, an 8-year-old schoolboy from Boston's Dorchester neighborhood, the youngest of those killed by blasts near the marathon finish line, was laid to rest Tuesday after a family-only funeral Mass. "The outpouring of love and support over the last week has been tremendous," the family said in a statement. "This has been the most difficult week of our lives." The Richards family said they would hold a public memorial service for Martin in the coming weeks.