By Natasja Sheriff

NEW YORK (Reuters) - Jurors deliberating murder and kidnapping charges against a man who confessed to strangling 6-year-old Etan Patz in 1979 ended a sixth day of deliberations on Wednesday without reaching a verdict in the notorious case.

Pedro Hernandez, 54, is on trial in the killing of Patz, whose disappearance from his New York City neighborhood nearly 36 years ago changed the way U.S. authorities respond to reports of missing or abducted children.

Patz was among the first children whose picture appeared on milk cartons in an effort to find them.

During the deliberations in state Supreme Court in Manhattan, the jurors asked Judge Maxwell Wiley for a list of all the witnesses and exhibits from the three months of testimony in the trial.

More than 50 witnesses testified. One the earliest was the boy's mother, Julie Patz, who took the stand in January.

The jury ended the day's deliberations without reaching a verdict and was scheduled to resume on Thursday morning.

Before retiring for the day, the panel also requested and heard a rereading of testimony by Chelsea Altman, a childhood friend who recalled Patz as "very curious and sweet and a little mischievous, but not a rebellious kid." 

She testified that Patz talked about wanting to go away with a friend he called Johnny.

In interviews with detectives in 1985, Altman said she thought Johnny was real, but on the witness stand she testified that she believed he was imaginary.

Hernandez's defense maintains is mentally ill and that the confession he gave police in May 2012 was coerced.

The prosecution maintains Hernandez is not mentally ill and that his confession was voluntary.

Patz disappeared on May 25, 1979 as he walked to his school bus stop alone in his Soho neighborhood for the first time. He has never been found, and he was declared dead in 2001.

Hernandez in 2012 confessed to choking the boy in a neighborhood deli basement and leaving a box with Patz's still-moving body in an alley.

Defense attorneys say the real killer is a longtime prime suspect, Jose Ramos, whose girlfriend once walked Patz and his friends home from school. Ramos is a convicted child molester in prison in Pennsylvania.

If convicted, Hernandez faces a maximum penalty of life in prison.

(Editing by Ellen Wulfhorst and Jonathan Oatis)