Boston Marathon bombing suspects initially planned July 4th attack

By Brian MacQuarrie, Maria Sacchetti, and David Filipov, Globe Staff

Dzhokhar Tsarnaev, the surviving suspect in the Boston Marathon bombings, told federal investigators that he and his brother initially planned to detonate explosives at Boston’s vaunted July 4th celebration on the Charles River Esplanade, according to two officials briefed on the interrogation.

When the brothers built the bombs faster than they had anticipated, they then drove around Boston and Cambridge sometime before Marathon day, casing police stations, with an alternative plan to launch an attack on law enforcement officers, one of the officials said.

“They surveyed these police stations, multiple stations in Boston and one in Cambridge,” said the official, who talked on the condition of anonymity.

“They built the bombs so fast that they decided to move the whole plan up,” the official said.

The fresh details from the Dzhokhar Tsarnaev interrogation with the FBI further enhances the notion of an oddly haphazard plot, one that ultimately focused on the homestretch and finish line of the Boston Marathon, the city’s most iconic sporting event.

Meanwhile, the lawyer for a Kazakh national charged with trying to destroy evidence in the bombing case said Thursday that his client turned over the bombing suspect’s laptop computer to the FBI four days after the deadly explosions.

The computer, which could hold key information about reasons and planning for the bombing, was handed to FBI agents during their first interview with Dias Kadyrbayev, according to his attorney, Robert G. Stahl.

Kadyrbayev, 19, was charged Wednesday with two other men in efforts to destroy or cover up evidence linking their college friend, Dzhokhar Tsarnaev, to the April 15 bombing. Tsarnaev’s friends are not accused of being involved with the bombing plot.

According to authorities, Kadyrbayev told them he took the laptop and a backpack from Tsarnaev’s dorm room at the University of Massachusetts Dartmouth after seeing Tsarnaev in photos released by the FBI on April 18 during a desperate search for the bombing suspects. Kadyrbayev helped discard the backpack, which held an array of fireworks, in a dumpster outside the pair’s New Bedford apartment, authorities said.

On Thursday afternoon, the body of Tamerlan Tsarnaev, Dzhokhar’s brother, was released from the state medical examiner’s office to an uncle, Ruslan Tsarni of Maryland, and Tamerlan’s two sisters, according to a Russian human-rights worker who is helping the family.

Tamerlan Tsarnaev, suspected of bombing the Marathon with his brother, died following a frenetic shoot-out with police in Watertown on April 19. Dzhokhar, who is believed to have run over Tamerlan with a car as he fled the shoot-out, later escaped on foot before being captured that evening.

Television helicopters followed the hearse they believed to be carrying Tsarnaev’s body to the Dyer-Lake Funeral Home and Cremation Services in North Attleborough. Funeral home managers did not respond to calls for comment on Thursday.

A cause of death will be made public once a funeral-service provider files a death certificate, said Terrel Harris, a spokesman for the office.

Kheda Saratova, the human-rights worker, said the Tsarnaev family does not intend to bury Tamerlan until they find an independent coroner to deliver an opinion. The Tsarnaevs have remained dubious of reports that police were taking Tamerlan into custody when Dzhokhar reportedly ran him over.

“The family is afraid that if Tamerlan is buried before they get all the answers, many secrets will be buried with him, and this will make it harder for Dzhokhar to defend himself in court,” Saratova said.

Dzhokhar Tsarnaev is being held at a federal prison hospital in Ayer. The three men charged with obstructing the investigation are being held at the Essex County Correctional Facility in Middleton.

The bombings killed three people and wounded more than 250 near the Marathon finish line on Boylston Street. Seventeen bombing victims remained hospitalized Thursday, including one child at Boston Children’s Hospital. None is in critical condition, one is listed as serious, and the rest are in fair or good condition.

The government of Kazakhstan said Thursday that officials there are cooperating with US authorities, but that “we would like to emphasize that our citizens did not receive charges of involvement in the organization of Boston Marathon bombings. They were charged with destroying evidence.”

The statement added, “As we have repeatedly stressed, Kazakhstan strongly condemns any form of terrorism.”