US authorities search several sites in Dartmouth as part of Boston Marathon bombing investigation

By Brian MacQuarrie, Globe staff

Federal authorities said they were searching various locations in Dartmouth today as part of the investigation into the Boston Marathon bombing.

The US attorney’s office said residents should be advised there is no threat to public safety.

The searches are being conducted by K9 units from Massachusetts State Police, Bureau of Alcohol, Tobacco, Firearms and Explosives along with numerous local departments, assisted by a State Police helicopter, law enforcement officials said.

Bombing suspect Dzhokhar Tsarnaev attended school at UMass Dartmouth and officials have conducted searches on the campus and a landfill in New Bedford in connection with the probe.

Tsarnaev was captured hiding in a boat in Watertown on April 19 after he escaped from a shootout with police. His brother Tamerlan was fatally wounded in the gun battle.

The Globe reported today that the brothers first planned to attack Boston’s Fourth of July celebration before abruptly changing their target to the Boston Marathon, where the detonation of two bombs killed three and wounded 264 people. The brothers are also suspected of murdering MIT Police Officer Sean Collier.

In the landfill search last week, authorities found a backpack belonging to Dzhokhar Tsarnaev and other evidence, according to court documents.

State and federal officials said they could not comment on the focus of today’s searches.

Investigators are also looking for further clues in the probe of two UMass Dartmouth classmates of Dzhokhar Tsarnaev who, along with a Cambridge man, have been charged with trying to destroy or cover up evidence linking Tsarnaev the bombings. Tsarnaev’s friends are not implicated in the actual bombing plot.

According to authorities, one of the friends, Dias Kadyrbayev, told them he took a laptop and a backpack from Tsarnaev’s dorm room 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 New Bedford apartment where he lived, authorities said.

Kadyrbayev’s attorney, Robert G. Stahl, has said his client did not know the backpack was connected to the Marathon bombings. Stahl also told the Globe that his client has handed over the laptop computer to the FBI.

The attorneys for the other two men have insisted their clients have not committed any crimes.