They wanted to shed more blood.
The Tsarnaev brothers were armed to the teeth while on the run and hoped to rack up the body count, authorities said Sunday.
The latest twist in the global investigation came as the surviving suspect in the Boston Marathon bombings, Dzhokhar Tsarnaev, regained consciousness Sunday night and began answering investigators’ questions in writing, ABC News and NBC News reported.
Investigators were eager to learn from the 19-year-old, who was seriously wounded in a shootout with cops Friday and unable to speak, if he and his brother had planted more bombs and if they were part of a larger terror cell.
“We have reason to believe, based upon the evidence that was found at that scene — the explosions, the explosive ordnance that was unexploded and the firepower that they had — that they were going to attack other individuals,” Boston Police Commissioner Ed Davis said earlier Sunday.
Multiple handguns, a rifle and at least six homemade bombs were recovered from the scene of the fierce Friday morning gun battle that led to the death of Tamerlan Tsarnaev, 26, in Watertown, Mass.
Watertown Police Chief Ed Deveau revealed the younger Tsarnaev killed his own big brother when he mowed him down with a stolen SUV while trying to escape the gunfight.
Dzhokhar Tsarnaev, poses for an undated photo after graduating from Cambridge Rindge and Latin High School.Tsarnaev, suspect in Boston Marathon bombing, is in the hospital after being captured by authorities on Friday.
“Quickly we had six Watertown police officers and two bad guys in a gunfight,” Deveau told the Boston Globe, adding that as many as 300 shots were exchanged.
Deveau said Tamerlan Tsarnaev, 26, walked toward officers with guns blazing, but apparently ran out of ammunition. Cops tackled him and were attempting to handcuff him, when the younger brother came roaring at them in a stolen SUV.
The chief said officers scattered and the SUV ran over Tamerlan, dragging him briefly. He died at a nearby hospital.
Dzhokhar Tsarnaev managed to drive a short distance before abandoning the SUV and running away. Hours later, he was cornered in the backyard of a Watertown house, hiding in the back of a boat.
While shots were exchanged, investigators believe Dzhokhar shot himself in the throat in a failed suicide attempt.
After the shooting stopped, the suburban streets of Watertown were like a minefield.
Tamerlan Tsarnaev (wearing a black baseball cap) and his brother Dzhokhar Tsarnaev (wearing a white baseball cap) are seen minutes before the Boston Marathon bombings.
Unexploded bombs were scattered around the scene, and authorities had to alert arriving officers to steer clear.
Deveau added that he’s convinced that the brothers whose bombs killed three people at last Monday’s Boston Marathon, then killed an MIT campus cop on Thursday night, were out for more blood.
“I think they were hell-bent on killing as many police officers as they could,” Deveau said.
A source claimed to Britain’s Daily Mirror that the FBI was hunting a 12-person terrorist “sleeper cell” that was being linked to the Tsarnaev brothers because of the sophistication of the explosives.
“They were too advanced. Someone gave the brothers the skills and it is now our job to find out just who they were,” the source told the newspaper.
But Boston Mayor Tom Menino immediately dismissed the story. “All of the information I have is they acted alone, these two individuals, the brothers,” Menino said.
Law enforcement officials are seen in front of 67 Franklin St after the capture of Dzhokhar Tsarnaev, the surviving suspect in the Boston Marathon bombings, in Watertown, Massachusetts April 19, 2013.
The Tsarnaevs’ intentions to continue to do harm emerged as the investigation focused on a trip Tamerlan took in secret to a Russian region known as a haven for Islamic extremist groups.
Authorities believe that mysterious seven-month sojourn likely holds the clues to unraveling what led the Tsarnaevs to seek the blood of Boston.
“I think it’s the linchpin to understanding if he or his brother acted on their own or were directed, guided, controlled by some foreign individual or entity,” Bruce Hoffman, a professor and terrorism expert at Georgetown University, told the Daily News.
Rep. Mike Rogers (R-Mich.), chairman of the House Permanent Select Committee on Intelligence, said Tamerlan “may have received training on what we ultimately saw last Monday” during his stay in Russia’s volatile north Caucasus region.
In other developments Sunday:
• It remained unclear whether Dzhokhar would ever speak again. CBS News cited sources saying he had likely put a gun in his mouth and attempted to shoot himself after he was cornered by cops. The bullet traveled out the back of his neck, leaving him bloody but alive.
James Keivom/New York Daily News
Cops hunt marathon bombers Dzhokhar (above l.) and Tamerlan Tsarnaev in Watertown, Mass. After Tamerlan was killed in shootout with police, his brother was captured Friday in a boat that cops aimed infrared viewing equipment at (right). Police then used high-tech tools to stun and trap him.
• Officials said Dzhokhar could be formally charged as soon as Monday. A judge would almost certainly charge him at Beth Israel Deaconess Medical Center, where the University of Massachusetts-Dartmouth student is bedridden and intubated.
• Massachusetts Gov. Deval Patrick told NBC’s “Meet the Press” that surveillance video captured Dzhokhar dropping a bomb-filled backpack and then walking away — a key piece of evidence for prosecutors building their case against him.
• Four candles accompanied by pictures of the four victims killed in the Boston bombings and subsequent shooting were placed on the altar at Boston’s Cathedral of the Holy Cross Sunday.
• Tamerlan’s widow, Katherine Russell, was “brainwashed” by the mastermind of the bombings, a friend who wouldn’t give her name told a reporter. By the time Russell was 21, she had dropped out of college, converted to Islam, married Tamerlan and had his baby, who is now 3.
“I saw her, like, a few months ago and she was just totally transformed. She was not the same person at all,” the friend told the Daily Mail.
Even before the elder Tsarnaev brother set out for Dagestan and Chechnya in January 2012, Tamerlan’s increasing radicalization had drawn the attention of the feds.
Russian authorities warned the FBI in early 2011 that Tamerlan “was a follower of radical Islam and a strong believer,” the agency said.
Tamerlan’s YouTube page was filled with jihadist videos, including clips of Abdul al-Hamid al-Juhani, a prominent Chechen extremist.
Read more: NY Daily News