A graphic photo of the dead body of Boston bomber Tamerlan Tsarnaev was leaked Friday evening.

The post-mortem photo was taken after his body was turned over to officials from medical personnel.

It is not known who has leaked the photo, but it has already been viewed by thousands as it went viral on sites such as Reddit.

The photo was taken at Boston's Beth Israel Deaconess Medical Center at 1:45 AM, according to The Smoking Gun.

26-year-old Tamerlan was shot to death in a shootout with police Thursday evening.

See the photo here. (WARNING: GRAPHIC, VIEW AT OWN DISCRETION)

The hospital's chief Dr. Richard Wolfe stressed that the photo had not been leaked by any members of his medical team.

The photo "was not taken during the medical procedures or when the medical team had control of the body," he said.

After the medical review, the corpse was handed over to law enforcement officials.

The photo shows the graphic gunshot wound that killed Tamerlan.

Meanwhile, police have finally captured his brother, 19-year-old Dzhokhar Tsarnaev, who was the run since Tamerlan was killed.

Dzhokhar's capture happened just before 9 p.m. ET on  Franklin St. in Watertown, Mass.

"He is in custody, he is alive and we are going to prosecute him and bring him to justice," a police officer said, according to a witness in the neighborhood who spoke to ABC News.

Dzhokhar was found hiding in a boat in the backyard of a residence on the street Friday evening, according to numerous media reports.

The arrest is the end of a day-long national manhunt for the suspect of the bombings Monday that killed 3 people, including a young boy.

The city of Boston had been on lockdown Friday and the streets resembled that of a ghost town as the suspect is believed to be extremely dangerous and possibly armed with a suicide bomb or other explosives.

Brothers Tamerlan and Dzhokhar planted two bombs at the Boston Marathon and killed a police officer Sean Collier at the MIT campus last night.