At least four people were killed and 51 injured in a car bomb blast outside the police headquarters in Egypt's capital Cairo Friday, a media report said.
The powerful blast was felt across the capital and black smoke could be seen rising over the city centre, BBC reported citing Egyptian health ministry.
The nearby Islamic museum and the National Archives building were also damaged, the report said.
Later, a second explosion took place in the city's Dokki district.
The blasts come on the eve of the third anniversary of the 2011 uprising that led to the ousting of the country's decades-long ruler Hosni Mubarak.
No group has claimed responsibility for the attacks.
