Image caption Prime Minster Peter O'Neill pledged to toughen laws in May, after several high-profile crimes

Papua New Guinea has repealed its controversial Sorcery Act but has expanded its use of the death penalty.

Under legislation passed in parliament on Tuesday, killings linked to allegations of witchcraft will now be treated as murder.

The death penalty will be applied to more crimes, including rape, and more methods of execution have been approved.

Amnesty International condemned the move to toughen penalties.

"Papua New Guinea has taken one step forward in protecting women from violence by repealing the Sorcery Act, but several giant steps back by moving closer to executions," Amnesty's deputy director for the Asia-Pacific Isabelle Arradon said in a statement.

'State-sanctioned violence'

In parts of Papua New Guinea, deaths and mysterious illnesses are sometimes blamed on suspected sorcerers, usually women. But officials say accusations of witchcraft are used to justify violence.

The repeal of the 1971 Sorcery Act, which acknowledged the accusation of sorcery as a plausible defence in murder cases, came after a series of brutal public killings.

In February, a 20-year-old mother accused of sorcery was burned alive in a village market. Two months later, a woman accused of black magic was beheaded.

Sorcery-related killings will now be treated as murder and the death penalty will be applicable, local media said.

Ms Arradon called the repeal of the act "long overdue" but accused the government of "attempting to end one of form of violence by perpetrating state-sanctioned violence".

Lawmakers have also approved legislation allowing the death penalty to be applied to aggravated rape - gang-rape, the use of a weapon, or rape of a child - and armed robbery, PNG's The National reported.

Parliament approved several methods for applying the death penalty, the Post Courier reported, including hanging, lethal injection, firing squad and electrocution.

Penalties for kidnapping, theft and white-collar crime were also toughened, with longer jail terms prescribed.

The laws were tough but reflected crime levels and community demands, The National quoted Justice and Attorney General Kerenga Kua as saying.

Papua New Guinea has not carried out an execution since 1954, despite parliament's decision to reintroduce the death penalty for murder in 1991. At least 10 people are currently on death row, Amnesty said.

PNG Prime Minister Peter O'Neil announced plans to begin implementing the death penalty and to increase prison sentences for violent crimes last month, saying "draconian" measures were needed.

His move followed a number of high-profile crimes in the Pacific nation, including the gang-rape of a US academic in April.