A suicide bomber struck Islamabad on the day thousands of Pakistanis marked the first anniversary of the storming of the Red Mosque. Warning: the following pictures contain disturbing images.
Earlier in the day, people performed ritual ablutions at the Red Mosque on the sidelines of a protest rally held by Islamists outside the compound.
Security was tight, as thousands of police were deployed around the gathering in front of the mosque. Protesters chanted slogans praising "martyrs" of the siege.
The suicide bomber struck as people were dispersing. Many of the dead were police officers.
At least 20 people were injured in the blast, which occurred in front of a police station.
The scene was covered with blood, and scattered body parts were found as far as 50 meters away.