Security guards and soldiers opened fire on stone-throwing protesters angry at an agreement calling for the ouster of the country's popular prime minister, killing two people.

Interior Minister Abdishakur Sheikh Hassan, who was also minister for national security, died after shrapnel hit his legs and other parts of his body, said Ministry of Information spokesman Abdifatah Abdinur. He said the body of the woman suspected to be the bomber was found in the home.

Mohamud Abdullahi Weheliye, a member of Parliament and a relative of Hassan, said the minister's niece carried out the attack and that she was "sent by Al-Shabab," a militia with ties to Al-Qaeda.

Abdinur said officials were investigating to confirm it was a suicide attack in the two-story, gated building that is normally well protected. The explosion took place in the living room.

"The walls of the living room cracked and blood and debris were scattered all over," said Mohamed Mohamud, a witness who visited the site after the explosion.

The violence came barely two days after President Sheikh Sharif Ahmed and the speaker of Parliament signed an internationally mediated agreement extending the government's term by a year. It postponed an August presidential election until 2012 to give leaders more time to deal with security and political issues.

In the wake of that agreement, things took a turn for the worse. Protesters blocked roads with rocks and burned tires, while chanting "Stay put Farmajo." Farmajo is Prime Minister Mohamed Abdullahi Mohamed's nickname. They also burned pictures of the UN envoy to Somalia whom they accused of pushing forward the agreement.