BOSTON (AP) — Boston Marathon bombing suspect Dzhokhar Tsarnaev returned to court Thursday for the first time since he was arraigned in July 2013.

Security was tight at the federal courthouse in Boston for the final pretrial conference before his trial begins next month.

Tsarnaev, 21, was led into the courtroom by U.S. marshals. He was wearing a black sweater and gray trousers and had a scruffy beard and a mop top hairstyle similar to the one seen in his mug shot. He smiled to his attorneys and one patted him on the arm.

Sketch of a shaggy Dzhokhar #Tsarnaev in Fed Court. First look in more than a year. pic.twitter.com/vVn3Jw5S3V — Dan Hausle (@dhausleon7) December 18, 2014

The courtroom was packed with FBI agents, police who worked on the case and more than a dozen survivors and family members.

Cameras were not allowed inside. Some Tsarnaev friends and supporters rallied outside the courthouse, holding signs that pleaded against sentencing the suspected bomber to death.

The hearing came to a close after just 25 minutes. After the judge and Tsarnaev had left he courtroom the mother-in-law of Ibragim Todashev started shouting in the courtroom, first in Russian and then in English.

“Stop killing innocent people,’’ Elena Teyer shouted. “Don’t kill an innocent boy, please!’’

Todashev, a friend of Tamerlan Tsarnaev’s, was shot and killed by an FBI agent in Florida after he allegedly confessed to committing a triple homicide in Waltham, a crime he allegedly said he committed with Tamerlan Tsarnaev.

Elena Teyer, mother-in-law of Ibrahim Todashev, after yelling her support for Tsarnaev in court today: pic.twitter.com/VomhOYCUrf — Adam Reilly (@reillyadam) December 18, 2014

Todashev's mother in law shouts in Russian and English as Tsarnaev exits courtroom. "Don't kill inconcent boys!" — Garrett Quinn (@GarrettQuinn) December 18, 2014

Three people were killed and more than 260 were injured when two bombs exploded near the finish line of the April 2013 marathon. Tsarnaev, who has pleaded not guilty to 30 federal charges, faces the possibility of the death penalty if he is convicted.

At his last court appearance nearly 1 1/2 years ago, Tsarnaev still bore signs of the bloody standoff with police that led to his capture and the death of his older brother, Tamerlan. His left arm was in a cast and his face was swollen. He appeared to have a jaw injury.

Thursday’s court hearing was the last one scheduled before jury selection begins Jan. 5. The trial is expected to last several months, and seating a jury alone could take several weeks to a month.

Judge George O'Toole Jr. questioned Tsarnaev about whether he had waived his right to appear at previous hearings. Tsarnaev answered in a clear voice: ‘‘Yes, sir.’’

Asked by the judge if his lawyers had acted in his best interests, he said: ‘‘Very much.’’

O'Toole said he remains concerned about disclosures in the media that possibly could have come from law enforcement sources. But he said prosecutors have responded to Tsarnaev’s lawyers’ complaints, reinforcing that officials shouldn’t be talking to reporters.

Prosecutors and defense attorneys were expected to discuss the jury selection process. Both sides have submitted questions they want the judge to ask potential jurors, who will be selected from a pool of at least 1,200 people.

A defense motion to move the trial out of Boston also is still pending. Earlier this month, Tsarnaev’s lawyers argued anew that ‘‘emotionally charged’’ media coverage and the widespread impact of the attacks have made it impossible for him to get a fair trial in Massachusetts.

O'Toole had rejected Tsarnaev’s first request in September to move the trial, ruling that defense lawyers had failed to show that extensive pretrial media coverage of the bombings had prejudiced the jury pool to the point that an impartial jury could not be chosen in Boston.

Tsarnaev’s lawyers previously said the trial should be moved to Washington, D.C.

O'Toole also rejected a defense request that prosecutors turn over evidence about his older brother’s possible participation in a 2011 triple killing in suburban Waltham.

Thursday’s hearing is the last conference between the judge, prosecutors from US Attorney Carmen M. Ortiz’s office, and Tsarnaev and his defense team. On the bench, O’Toole said he wanted to get as much information as possible on the public record, but he must keep some matters sealed, including the proposed witness list.