Blasts in Cairo's Ain Shams district, Egypt, February 7, 2014.
CNN  — 

At least three police officers were injured in twin blasts in Cairo Friday, Egyptian state media reported.

The explosions took place on a bridge in the Egyptian capital and targeted a police check point, according to state media.

Instability has raged in Egypt since the military toppled democratically-elected Mohamed Morsy last year. Security forces have also cracked down on the Islamist movement that supported him, the Muslim Brotherhood.

Last month, a powerful explosion hit the police headquarters in Cairo. It struck a key symbol of authority in a country shaken by political turmoil and violent unrest in recent years.

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