Amnesty International has called on Pakistan's government to ensure the killers of Shahbaz Bhatti, the country's minister for minorities, are brought to justice.
Bhatti, the only Christian member of the cabinet and one of the country's few leading politicians calling for changes to the country's controversial blasphemy laws, died today after three armed men opened fire on his car as he travelled to work in the capital, Islamabad.
"The Pakistani government must act immediately to bring the assassins to justice in a trial that meets international standards. Continued lack of accountability for perpetrators of abuse has severely eroded the rule of law in Pakistan," said Sam Zarifi, Amnesty International's Asia-Pacific Director.
Bhatti had previously received threats from groups opposed to reforms of the blasphemy laws.
The assassination follows the January killing of Salman Taseer, the governor of Punjab province, and another outspoken critic of the law.
"Such violations thrive in the atmosphere of impunity and irresponsibility fostered by the government's failure to uphold its human rights obligations," said Sam Zarifi.
"The government must avoid the faulty forensic practices that have marred previous investigations, such as in the cases of Taseer and former Prime Minister Benazir Bhutto."
The Pakistani Taleban have reportedly claimed responsibility for killing Bhatti and warned others who have criticized the blasphemy laws that they will meet the same fate.
Several critics of the blasphemy law have received death threats in the past two months.
Members of religious minority groups have told Amnesty International that they face increasing threats from extremist groups.
"It is ultimately the responsibility of the Pakistan government to protect its citizens from violence committed by extremist groups. President Zardari – and the security forces – must increase protection to all Pakistanis who have called for reform of the country’s blasphemy laws," said Sam Zarifi.