It was a massive blast - killing dozens and injuring hundreds in the heart of Islamabad, Pakistan's capital.
The blast at the US-owned Marriott hotel comes after Pakistan's new government vowed to increase the pressure on al-Qaeda-linked fighters.
Asif Ali Zardari, Pakistan's president, has vowed to rid his country of what he called "the cancer of terrorism".
Al Jazeera's Imran Khan reports.
