NEW YORK – U.S. police announced on Wednesday the arrests of three more suspects as part of the investigation into a bomb attack at the Boston marathon that left three dead and more than 260 wounded.
“Three additional suspects were taken into custody in the [Boston] marathon bombing case. Details to follow,” the Boston Police Department said on Twitter, later adding: “Please be advised there is no threat to the public.”
One of two ethnic Chechens, 19-year-old Dzhokhar Tsarnaev, is already in custody and has been charged with carrying out the bombing.
His brother, 26-year-old Tamerlan Tsarnaev, was killed on April 18 during the manhunt for the pair.
The brothers are alleged to have detonated backpacks holding pressure cookers packed with explosives near the finish line of the April 15 race. They are also accused of killing a police officer during their time on the run.
Police did not immediately offer more details of the arrests, but the Boston Globe newspaper reported that the new suspects were college students who are alleged to have helped Dzhokhar after the attack.
Television network NBC reported the new suspects are accused of helping their fellow student gather his belongings from his campus accommodation and may have attempted to mislead authorities.
U.S. authorities are investigating a recent period Tamerlan spent in the volatile North Caucasus region of Russia and intelligence reports that he had developed an increasingly radical view of his Islamic faith.
But investigators have not suggested the pair were part of a larger group.
U.S. lawmakers have said the pair’s mother, Zubeidat Tsarnaev, is suspected of playing a role in radicalizing them. She is currently in the Dagestan region of Russia and denies that her sons had any role in the bombing.
Police also searched the home of Tamerlan Tsarnaev’s widow, 24-year-old Katherine Russell, after female DNA was found on debris from the pressure cookers.
U.S. President Barack Obama has defended the counter-terror work of the FBI, after it was revealed that Russian authorities had warned the U.S. agency as early as 2011 that Tamerlan Tsarnaev had suspected extremist ties.