The four men convicted in the brutal rape and murder of a young woman last December on a bus in New Delhi were sentenced to death on Friday. Here's a timeline of the story that shocked and outraged India:

Dec. 16, 2012: A 23-year-old female student and her male companion are assaulted aboard a bus in New Delhi. The woman is gang raped as the bus moves through Delhi streets, passing several police checkpoints. She and her friend are thrown from the bus, naked, and eventually taken to the hospital.

Dec. 17, 2012: Delhi police identify and arrest four of the accused attackers, while the victim remains in critical condition. Protests begin in Delhi and continue for weeks, turning violent at times. In subsequent days, police arrest two more suspects.

Dec. 26, 2012: The victim is flown to Singapore after her condition deteriorates suddenly and she suffers cardiac arrest. She dies three days later, succumbing to massive internal injuries.

Jan. 2, 2013: India's chief justice inaugurates fast-track courts to deal with rape cases.

Jan. 3, 2013:Police submit charges against five of the accused: driver Ram Singh, his brother Mukesh, Pawan Gupta, Vinay Sharma and Akshay Thakur. The charges include murder, gang rape, kidnapping, unnatural offenses, destruction of evidence, criminal conspiracy and common intention. The sixth suspect is exempted from the charges after he is found to be a minor who was 17 at the time of the crime.

Feb. 5, 2013: The trial for the five adults officially begins.

Feb. 28, 2013:The Juvenile Justice Board opens an inquiry against the sixth defendant, who was 17 at the time of the crime. The accused pleads not guilty to a host of charges that include rape and murder.

March 11, 2013: A man accused in the case, Ram Singh, is found hanging in his jail cell. Suicide and foul play are both alleged.

April 2, 2013: A stricter sex-crime ordinance comes into effect. Among other measures, it increases punishment for rapists to life in prison or the death penalty, in the case of the death of a victim or permanent vegetative state. Gang rape now carries a minimum sentence of 20 years.

July 5, 2013: The inquiry concludes against the juvenile, whom police allege was the most brutal of the accused.

Sept. 3, 2013: The judge closes the trial of the four remaining adult defendants, rejecting any more petitions that he says have delayed the fast-track court. Over the course of seven months, more than 80 witnesses took the stand.

Aug. 31, 2013: The juvenile defendant in the case is found guilty of rape and murder and given the maximum sentence, three years. Counting the time he's been detained, he will serve 28 months in a reform home. The sentence provokes widespread outrage.

Sept. 10, 2013: The four adult defendants are convicted of rape, murder and other charges.

Sept. 13, 2013: The four are sentenced to death, a penalty rarely handed down in India.

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