The five men accused of the rape and murder of an Indian medical student have pleaded not guilty to charges, as the nation's cabinet approved harsher penalties for rapists - including the death penalty.

Police say the gang lured the 23-year-old woman onto a bus in New Delhi where they repeatedly raped and assaulted her with a metal bar before throwing her onto a highway.She died of internal injuries two weeks after the attack in December."After the judge read out the charges, the five pleaded not guilty and walked out" said lawyer AP Singh on Saturday, who is defending two of the accused.Mr Singh said the prosecution will call three witnesses to the next hearing on Tuesday, which is the formal start of the trial.The prosecution says it has strong evidence against the five men, including blood-stained clothing, DNA matches, mobile phone records, confessions and eye-witness statements.