The World Council of Churches (WCC) is reiterating its 2009 call to repeal Pakistan's blasphemy law after two Christian brothers were killed in Faisalabad earlier this week.

Pastor Rashid Emmanuel and his brother Sajid Emmanuel were shot to death on Monday by unidentified gunmen outside of a courtroom where they had just been acquitted of blasphemy charges.

According to local officials, mosques had been calling for the brothers to be attacked after leaflets bearing their names and derogatory remarks about Muhammad had been circulated.

WCC General Secretary the Rev. Olav Fykse Tveit said that he received news of the killings with "great dismay" and accused the blasphemy law of being "fraught with danger that can be abused by extremist groups when dealing with religious minorities."

"It has been proven in the past that the charges of Blasphemy law appear to be arbitrarily applied and at times founded on malicious accusations against individuals and groups," Tveit wrote in a letter to Pakistan President Asif Ali Zardari and Prime Minister Syed Yousaf Raza Gilani.

Tveit further noted that the law is a violation of fundamental rights guaranteed by Article 36 of Pakistan's Constitution, and made a plea to the officials to "ensure immediate and necessary actions to bring to justice" those responsible for Monday's killings.

"We also urge Your Excellency to initiate measures towards the repeal of the Blasphemy Laws and to secure the rights and dignity of all individuals in Pakistan society," Tveit said, echoing the WCC's September 2009 statement on the law.

According to the WCC, there are about 4.2 million Christians in Pakistan, many of whom live under threats from radical Muslims in the Taliban and al-Qaeda.

Other groups, including the Anglican Communion, have also called for the country's blasphemy law to be repealed.