By Natasja Sheriff

NEW YORK (Reuters) - Jurors began a fourth day of deliberations on Monday in the murder trial of a man who confessed to strangling 6-year-old Etan Patz in 1979, one of the first cases to highlight the plight of missing and abducted children.

Pedro Hernandez, 54, is charged with kidnapping and murdering Patz, who vanished as he walked alone for the first time to a school bus stop in his Manhattan neighborhood.

The boy's picture was one of the first to appear on milk cartons in a campaign to locate missing children.

Hernandez confessed to police in 2012 that he choked Etan, stuffed him in a box and left him in a New York alley.

Defense attorneys say the confession was coerced and that Hernandez, arrested on a tip that he had confessed to a church prayer group, is mentally ill, intellectually disabled and suffers hallucinations.

During deliberations on Friday in state Supreme Court in Manhattan, the jury asked to examine a missing-child poster featuring the boy, which had been introduced as evidence.

Hernandez, a former Manhattan deli worker, at the request of police had written on the poster: "I am sorry (and) choke him."

The decades-old case, which still evokes strong passions in New York, came to represent the dangers of living in the city at a time when crime rates were surging.

Patz has never been found and was declared dead in 2001.

The jury asked to see a copy of Hernandez' signed statement that he understood his right to remain silent and another statement written by detectives and signed by Hernandez, the substance of which was unclear.

The jury started hearing testimony in January. No forensic evidence was presented at trial.

In his confession to police, Hernandez described luring Patz into the deli where he worked, taking him to the basement and strangling him.

Defense attorneys put blame on Jose Ramos, whose girlfriend at the time used to walk Etan and his friends home from school. Long the prime suspect, Ramos is a convicted child molester in prison in Pennsylvania.

If convicted, Hernandez faces the possibility of life in prison.

(Editing by Ellen Wulfhorst and Bill Trott)