Bomb suspect wakes up: He is conscious and answering FBI questions in writing after 'shooting himself through mouth on boat'

Dzhokhar Tsarnaev is responding sporadically in writing to questions from investigators regarding other cell members and other unexploded bombs

Teenager may have had no intention of being taken alive

Dzhokhar and his older brother Tamerlan may have had suicide pact to prevent them from being put on trial, police sources tell MailOnline

Condition downgraded to 'critical but stable' from initial reports that he was 'serious'



Tsarnaev had lost large amounts of blood by the time he was captured

Suffered a gunshot to the throat and a wound to his leg

Massachusetts Governor reveals video shows Tsarnaev planting second bomb at marathon

Police commissioner says suspects were planning another bomb attack when they were caught




Alleged Boston Marathon bomber, Dzhokhar Tsarnaev, is awake and responding to questions in his hospital bed.

The 19-year-old is responding sporadically in writing to questions from investigators regarding other cell members and other unexploded bombs, law enforcement officials said.



Agents are quizzing Tsarnaev about whether he had any accomplices who helped him carry out his attacks.



The news comes as it is revealed Tsarnaev, who is badly wounded in the throat, meekly pulled up his shirt to show officers that he was not wearing a vest strapped with explosives on Friday night as he emerged from the boat he had been cowering in.

'At the end they were just making demands of him: Show your hands, lift your shirt. And eventually that's what he did,' Watertown Police Chief Edward Deveau told ABC News .



'He was very slow and lethargic in every move that he made and they could see that there was no device on his chest. They kept creeping closer to him and then they felt it safe enough to pull him away from the boat.'



Authorities initially said they couldn't question the terror suspect because of his severe throat wound .



Tsarnaev is believed to have shoved his pistol in his own mouth and pulled the trigger in a failed suicide attempt as SWAT officers and federal agents closed in on his backyard hiding place. However, instead of killing him, the bullet simply tore through his neck.

CNN reported earlier today that Tsarnaev was 'intubated and sedated' at a Boston hospital.

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Wounded: Dzhokhar Tsarnaev, seen here moments after he was pulled from the boat where he was hiding, suffered a throat wound and a leg wound

Wounded: Tsarnaev was immediately loaded into an ambulance and rushed to the hospital, where he remains in serious condition

Site: A blood stain can be seen on the boat where Dzhokhar Tsarnaev was found hiding after a massive manhunt that left the Boston area paralyzed in fear Hiding out: This is a surveillance video image of Tsarnaev getting out of the boat where he was pinned down on Friday night

The Boston police commissioner said Tsarnaev is in 'critical but stable' condition on Sunday - which appears to be a downgrade from reports earlier this weekend that his condition was only 'serious.'

Boston Mayor Tom Menino had earlier feared that federal agents would never be able to interview Tsarnaev but it seems that investigators may already be making progress.

Police sources told MailOnline that investigators are looking into the possibility that Tsarnaev and his older brother Tamerlan had a suicide pact so that neither of them could be taken alive and put on trial. Authorities believe Dzhokhar likely killed him brother, who was handcuffed, when he ran over him.

A suicide pact could also explain why 19-year-old Dzhokhar ran over his own brother in his stolen Mercedes SUV as he escaped from the scene, the sources added.



Tamerlan was killed early Friday after a running gun battle with police. Doctors say he appeared to have multiple gunshot wounds, blast injuries and major trauma from being hit and dragged by his brother's car.



The new twist in the story of Tsarnaev's dramatic capture comes as the Boston police commissioner warns that he and Tamerlan were plotting more bomb attacks on the city and they were caught just in time. Authorities insisted that the pair were working alone.

Ed Davis said the bombers were flushed out of hiding when the FBI released close-up surveillance video of their faces and asked for the public's help in tracking them down.

'The news conference forced them out of their hideout and they decided to commit further violent acts. But it’s my belief that they were already manufacturing explosive devices. Further violent acts were inevitable,' Davis told The Boston Globe .



New video also revealed the final moments of Dzhokha's standoff with police. The images come from a thermal imaging camera aboard a Massachusetts State Police helicopter that was hovering above the dramatic police standoff.

Tsarnaev, 19, was captured by police on Friday night after the boat's owner found him hiding out when he went to check on his beloved watercraft in that was parked on a trailer at a house in suburban Watertown, Massachusetts.



Dzhokhar Tsarnaev is awake and responding to questions. Authorities are anxious to talk to him to learn his motives behind the attack

Still: The suspect appears to be laying flat in the boat in the final moments before his capture

In hiding: The dramatic footage released by police shows where the teenager lay hiding in a boat in the quiet suburban neighbourhood of Watertown

Blast: Video appears to show a flash grenade being thrown into the boat where the suspect hid

Show of force: The Massachusetts State Police has released this video showing an explosion resulting from a grenade thrown into the boat where the suspect lay

It is believed that federal prosecutors are putting the final touches together on charges against Dzhokhar Tsarnaev and could filed them today.



The most serious charge available to federal prosecutors would be the use of a weapon of mass destruction to kill people, which carries a possible death sentence. Massachusetts does not have the death penalty.

Massachusetts Governor Deval Patrick revealed on Sunday that s urveillance video from the Boston Marathon attack shows one suspect dropping his backpack and calmly walking away from it before the bomb inside it exploded.



'These guys did not have an exit plan after the bombing, and from they way they have both ended up it looks like they planned on never being taken alive.



'Why else would this kid drive over his brother. It does not make any sense until you realize he also tried to take his own life. They had some sort of suicide pact worked out so they would not be taken alive.'



Police source speaking to MailOnline



The video clearly puts 19-year-old Dzhokhar Tsarnaev at the scene of the attack, Patrick said on NBC.

'It does seem to be pretty clear that this suspect took the backpack off, put it down, did not react when the first explosion went off and then moved away from the backpack in time for the second explosion,' Patrick said. 'It's pretty clear about his involvement and pretty chilling, frankly.'

Tsarnaev reportedly lost significant amounts of blood after suffering two wounds. One was a gunshot to the leg he sustained during a running gun battle with police early Friday. Another was the wound to his neck.

CBS News correspondent John Miller reports: 'They say it appears from the wound that he might have stuck a gun in his mouth, and fired and actually just went out the back of his neck without killing him.

'That's one of the reasons he's unable to communicate, but he can understand what they're saying. And they believe there will be a point where he will be able to talk to him.'

Law enforcement sources tell MailOnline that Tamerlan and Dzhokhar Tsarnaev were determined not to be taken alive.

Dzhokhar was also responsible for driving over his brother as he was being handcuffed by police following a fierce gun battle in Watertown in the predawn hours of Friday.

The teen floored a stolen Mercedes SUV and drove it straight at the police and his 26-year-old brother who was on the ground after being seized.

The police were able to jump out of the way - but Tamlerlan was dragged for up to 40 feet under the wheels of the speeding car.

Dzhokhar Tsarnaev and his 26-year-old brother Tamerlan 'were going to attack other individuals' —says Boston police commissioner Davis and says that opinion is based on the evidence at the scene and the cache of weapons the brothers had at their disposal.



Planning further atrocities?: Dzhokhar Tsarnaev and his 26-year-old brother Tamerlan were believed to be about to unleash further terror attacks on Boston according to the city's police commissioner

The crush injuries are thought to have contributed to his death but police have yet to reveal an exact cause of death.

'These guys did not have an exit plan after the bombing, and from they way they have both ended up it looks like they planned on never being taken alive,' said a law enforcement source.

'Why else would this kid drive over his brother. It does not make any sense until you realize he also tried to take his own life. They had some sort of suicide pact worked out so they would not be taken alive.'



Exactly what happened in the boat remains unclear. Neighbors reported hearing police SWAT officers unleash several bursts of automatic weapons fire as they closed in on the 25-foot vessel.



A police robot tore open the cover of the boat and a state police helicopter used an infrared camera to reveal Tsarnaev's location in the stern.

Officers lobbed flash grenades into the boat in attempt to stun the suspect and called from him to surrender.



He later climbed out of the boat and surrendered.



After he was taken into custody, he was rushed to the hospital.



Suspects: Tamerlan Tsarnaev, 26, left, was reportedly run over by his accomplice and younger brother Dzhokhar Tsarnaev, 19

Evidence: Investigators gather evidence on Saturday, near the location in Watertown, Mass., where Dzhokhar Tsarnaev, 19, was captured