Bomber 'put gun in his mouth and fired as he was cornered in boat' and wounds mean he may NEVER be able to be quizzed

The alleged Boston Marathon bomber may have tried to kill himself rather than surrender after he was cornered by police - but failed in his suicide attempt, it has been revealed. 

A new report says Dzhokhar Tsarnaev shoved his pistol in his own mouth and pulled the trigger as SWAT officers and federal agents closed in on the boat where he was hiding on Friday night. However, instead of killing him, the bullet simply tore through his neck. 

Authorities have said they cannot question him because of the throat wound. CNN reports that Tsarnaev remains 'intubated and sedated' at a Boston hospital.

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

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 revealed that federal agents may never be able to interview Tsarnaev. Menino didn't elaborate on his comment and it is unknown whether the gunshot also caused brain damage.

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

Hiding out: This is a surveillance video image of Tsarnaev getting out of the boat where he was pinned down on Friday night

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.