Six people have been killed and some 100 others wounded in a series of explosions in the Egyptian capital of Cairo.
A powerful car bomb exploded outside the police headquarters in central Cairo on Friday morning, killing four people and wounding at least 76.
Hours later, there were three more blasts elsewhere in the city, killing two people and injuring several more.
The attacks come on the eve of the third anniversary of the 2011 uprising.
The revolution forced the country's decades-long ruler Hosni Mubarak to resign.
An al-Qaeda-inspired militant group Ansar Beit al-Maqdis (Champions of Jerusalem) has said it carried out the attack on the police headquarters.
The group previously claimed responsibility for a car bomb attack on a security building in the northern city of Mansoura in December that killed 16 people and injured more than 100 others.
The authorities blamed the Muslim Brotherhood for that attack - something the group strongly denied - and declared it a terrorist group shortly afterwards.
An angry group gathered outside the bombed police headquarters, accusing the Islamist movement of being behind Friday's attacks. Some shouted "Death to the Muslim Brotherhood."
The Muslim Brotherhood condemned what it called the "cowardly bombings".
The police headquarters was hit by a powerful blast at about 6:30 a.m. local time. Black smoke could be seen rising over the city soon after.
Egyptian Interior Minister Muhammad Ibrahim said it appeared to be the work of a suicide bomber.
Read the full story and updates at BBC News.