Boston Marathon bomber Dzhokhar Tsarnaev gave a stunning courtroom apology when he was sentenced to death in the deadly 2013 attack, but just after he was captured, he showed "the opposite of remorse," prosecutors said in court documents released Wednesday.

Tsarnaev, 22, was convicted last year and sentenced to die for his role in an attack that killed three people and injured more than 260. At his sentencing hearing, he said he was sorry for the lives he took and the suffering he caused.

In newly released court documents, prosecutors said Tsarnaev expressed anything but regret when he was questioned by two FBI agents after his capture days after the bombings. They included the description of Tsarnaev in a motion to limit the testimony of Sister Helen Prejean, a Roman Catholic nun and staunch death penalty opponent made famous by the 1995 film, "Dead Man Walking."

Prosecutors argued that Prejean's testimony should be excluded, calling it a "thinly disguised way for Tsarnaev to offer statements of remorse" without having to make them under oath, be cross-examined by prosecutors and allow jurors to gauge his sincerity for themselves. They argued that if Prejean was allowed to testify, they should be allowed to confront her with other statements Tsarnaev made to FBI agents after his capture.

Tsarnaev's actual statements to the FBI agents or to Prejean were not released publicly. They are included in hundreds of other court filings that have not yet been released because prosecutors or Tsarnaev's lawyers have asked that they remain sealed. More than 600 court filings and exhibits are being made public this week, but many more will remain sealed until the judge rules on their release.

Prejean was allowed to testify. She said Tsarnaev expressed genuine sorrow about the victims of the bombing, quoting him as saying, "No one deserves to suffer like they did."

During his sentencing hearing, Tsarnaev apologized to the victims and their loved ones. "I pray for your relief, for your healing," he said.

But during the trial, prosecutors showed the jury a photo of a defiant Tsarnaev giving the middle finger to a security camera in his jail cell three months after his arrest.

The documents released Wednesday also included some of the statements Tsarnaev made as he was being questioned by FBI agents in the hospital after he was captured. At the time, Tsarnaev was critically injured with multiple gunshot wounds following a shootout with police in Watertown and his capture inside a boat that police sprayed with bullets.

Tsarnaev repeatedly asked about the condition and whereabouts of his older brother, Tamerlan, who carried out the bombings with him and died following the shootout with police. By the time he was questioned, Tamerlan Tsarnaev had been dead for nearly two days.

A defense motion to suppress statements he made in the hospital said it was "apparent that the agents falsely told him that Tamerlan was alive."                                  

Tsarnaev, who was unable to speak because of a throat injury, wrote down his answers to the agents' questions. One of his notes read: "Is my brother alive I know you said he is are you lying Is he alive? One person can tell you that," according to the unsealed documents.

Another note read: "Is he alive, show me the news! Whats today? Where is he?"

The motion also said Tsarnaev repeatedly asked for a lawyer as he was questioned on and off over a period of 36 hours. It also said he told investigators that no one other than his brother was involved and there were no remaining bombs.