No organization has claimed responsibility for the attack that was aimed at the security forces that were deployed for the security of the conference at the Red Mosque which has become an icon after the military operation.

Dozens of religious leaders from across the country and more than 3,000 people, mostly students from seminaries, attended the conference and held rally at the Red Mosque, Islamabad. Around 4,000 policemen were deployed to guard the venue for the rally.

Security forces surrounded the mosque on July 3, 2007 following clashes between the police and the seminary students, who had abducted several women alleging them to be prostitutes and threatened music shop owners to give up the trade under an 'anti-vice' campaign.

A week later the Special Services Group (SSG), the elite strike force of the Pakistan Army stormed the mosque in a pre-dawn operation. According to the government 100 people, including 12 soldiers, were killed in the eight-day operation. Abdul Rashid Ghazi, younger of the two brother clerics of the mosque, also died while fighting the troops. The elder brother, Abdul Aziz, was arrested a few days before the final assault. He remains in police custody since then.

Supporters of Red Mosque say the real death toll was much higher, possibly in thousands.

The operation is considered a significant incident in the recent history of militancy in Pakistan, as it was followed by a series of suicide attacks on security forces which killed more than 3,000 people during the past year.

Though backed by Pakistani liberals, the mosque action remained highly unpopular among the general public and became one of the reasons for the defeat of Musharraf's political allies in February 18 elections. Emotions were still running high a year later. To borrow National Assembly member, Ayaz Amir, “as a candidate in the election I can testify to the emotive impact on the minds of people of the Lal Masjid and Jamia Hafsa operation. A mention of it and audiences would become emotional, even to the extent of having to dry their eyes.”

One of the causes of militancy in Swat is related to the Red Mosque operation since most of the boy and girl students at the seminary were from Swat and other parts of the NWFP.

It is not clear who may be behind the Sunday suicide attack. There are three theories:

1. According to Adviser to the Prime Minister on Interior, Rehman Malik, it was the latest revenge attack for the storming of the Red Mosque.

2. Many believe that attack may be a response from the FATA militants who had threatened to take revenge for a paramilitary operation against the militants in the Khyber Agency. The operation was suspended on Saturday amid mounting opposition from the opposition as well as ruling coalition partners. The operation has also created a rift in the fragile coalition that completed its first 100 days this week. Pakistan Muslim League-N of the former Prime Minister Nawaz Sharif, a coalition partner, has disassociated from the military operation by saying that it was not consulted by its major coalition partner the Pakistan People’s party. Maulana Fazalur Rehman, leader of JUI-F, a minor coalition partner, has demanded a halt to the military operation.

The Awami National Party (ANP), which is a coalition partner at the center and has its government in the volatile NWFP province, has reportedly threatened to quit the coalition on the issue of military operation. The ANP is against any military operations in the tribal territories. After taking power in the province, it embarked on peace negotiations with the militants and concluded at least two deals in Swat and Malakand Agency. However, the peace deals were not liked by the United States which pressurized a compliant Federal Government and Pakistan Army (which remains the main power broker despite an elected government and a toothless parliament) to launch military operation against the militants.

3. Yet many others believe that certain external forces are trying to destabilize the country through such attacks.

The latest bombing comes after a period of relative calm, with the country’s newly elected government adopting a strategy of political negotiations and development to bring an end to the militancy. This was the second major bombing in Pakistan's capital in a little more than a month. On June 2, at least eight people were killed and scores injured when a car bomb exploded in front of the Danish Embassy.