At least one French tourist was killed and 20 people were wounded in a blast in Cairo's populous al-Hussein district on Sunday evening, the Health Ministry said in a statement.
A French woman died in hospital of wounds sustained in the explosion, which happened on a small square between the al-Hussein mosque and the Khan al-Khalili bazaar, a tourist attraction, at 6:50 p.m. local time (1650 GMT).
The 20 injured, one of them in critical condition, included 13 French tourists, three Saudis and four Egyptians, said the statement, adding that they were rushed to five nearby hospitals for treatment.
According to Egyptian Attorney General Abdel-Hegid Mahmoud, who has inspected the scene, the body of the French woman would be handed over to the French Embassy in Cairo.
Police have cordoned off the scene of explosion and investigation is under way as high-level security officials arrived at the area soon after the explosion.
Security forces were combing the place with explosive detectors and sniffing dogs.
Blood could be seen on the small square and tourists have been evacuated and shops and cafes in the area were shut down for fear of further attacks.
Local Nile TV quoted witnesses as saying the explosion occurred after two suspects, hiding in a nearby building, threw two bombs at the crowd. One bomb went off at the scene and the police defused the other.
But the state MENA news agency quoted a security source as saying that the explosive might have been hidden under a stone bench in the area.
Egyptian President Hosni Mubarak was highly concerned about the conditions of the victims and has ordered prompt treatment for the wounded, the news service added.
The Grand Imam of al-Azhar University Sheikh Mohamed Sayyed Tantawi, Egypt's top cleric, condemned the bombing as a "cowardly criminal act."
"(The blast's) perpetrators are traitors to their nation," the MENA quoted him as saying, adding that, "Islam has nothing to do with such terrorist and irresponsible actions."
Attacks against foreign tourists frequently haunted Egypt, where tourism is the prime earner of foreign money and contributes about 8.5 percent of GDP.
In April 2005, two French tourists were killed and 18 others wounded in a suicide attack in the same area.
On April 24, 2006, three bomb blasts in the Egyptian Red Sea resort of Dahab killed at least 23 people and wounded scores of others.
On July 23, 2005, two car bombs and a suitcase bomb struck hotels and shopping areas in the Red Sea resort of Sharm el-Sheikh, killing at least 64 and wounding more than 200, including some foreigners.