Two policemen were injured in a bomb attack that struck central Cairo on Tuesday morning, state television reported.
Those behind the blast are as yet unidentified. They targeted a traffic police checkpoint, according to Reuters.
Since Muslim Brotherhood leader President Mohamed Morsi was ousted from power in July last year, Islamist militants have significantly increased their attacks on Egypt's security forces, killing hundreds.
Where Islamist insurgency used to be largely limited to the restive Sinai Peninsula, it has currently spread to Egypt's capital and other cities across the Arab world's most populous state, according to Reuters.
Former Defense Minister Abdel Fattah al-Sisi, who was key in ousting Egypt's first democratically elected president from office, yesterday officially submitted his bid for presidency. He is expected to win the poll, which will take place in July.