Boston Marathon bombing suspect Dzhokhar Tsarnaev admitted his involvement in the plot to investigators before being read his Miranda rights, government sources said.
Members of Congress briefed by law enforcement told Reuters that Tsarnaev said he and his brother acted without assistance from any foreign or domestic militant groups.
Tsarnaev said his older brother, Tamerlan, asked him to participate in the April 15 bombings only recently, according to the Associated Press.
After being advised of his constitutional rights, Tsarnaev stopped talking, the AP reported. He was questioned for about 16 hours.
The brothers are accused of planting two pressure cookers filled with explosives near the marathon finish line on Boylston St. Three people were killed and more than 250 injured in the blasts.
Tamerlan Tsarnaev, 26, was killed in a shootout with police three nights after the bombings. Dzhokhar Tsarnaev was captured the next night, after an all-day manhunt that shut down the Boston area.
Meantime, members of the MBTA SWAT team that helped arrest the 19-year-old said the suspect did not appear to have a weapon when he was taken into custody.
In an interview with the Boston Globe, officers said Tsarnaev was barely conscious.
“He looked like a bloodied-face suspect in need of medical care,” SWAT team member Kenny Tran told the Globe.
Law enforcement officials also said a wound on Tsarnaev's neck did not look self-inflicted.
SWAT team member Jeff Campbell told the Globe that the 2-inch-long wound could have been caused by shrapnel from an explosion.
Tsarnaev is recovering under police guard at Beth Israel Deaconess Medical Center.
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