An Egyptian riot policeman holds his weapon during clashes with supporters of ousted President Mohammed Morsi in Matariya Square, Cairo, Egypt, Thursday, Aug. 14, 2014 (Photo: AP)
An Egyptian woman covers her mouth from heavy smoke after supporters of ousted President Mohammed Morsi blocked a road by setting waste on fire in Matariya Square, Cairo, Egypt, Thursday, Aug. 14, 2014 (Photo: AP)
Security was tightened on Thursday, which was the one-year anniversary of the clearing of the Muslim Brotherhood sit-in at Cairo's Rabaa al-Adawiya, where at least 817 protesters were killed when security forces stormed two protest camps Cairo August 14, 2014 (Photo: Reuters)
Egyptian supporters of ousted President Mohammed Morsi block a road by setting waste on fire in Matariya Square, Cairo, Egypt, Thursday, Aug. 14, 2014 (Photo: AP)
A bomb detonation expert walks in his suit next security personnel before defusing a bomb found in an area in Giza, south of Cairo August 14, 2014 (Photo: Reuters)
A bomb detonation expert walks in his suit next security personnel before defusing a bomb found in an area in Giza, south of Cairo August 14, 2014 (Photo: Reuters)
A bomb detonation expert walks in his suit next security personnel to defuse a bomb found in an area in Giza, south of Cairo August 14, 2014 (Photo: Reuters)
A bomb detonation expert in his suit (R) is accompanied by security personnel as he defuses a bomb found in an area in Giza, south of Cairo August 14, 2014 (Photo: Reuters)
A soldier stands guard in a tank in Tahrir square in Cairo August 14, 2014 (Photo: Reuters)