Protesters and police marked the fourth anniversary of the 2011 uprising Sunday with violence leaving at least 13 people dead in Egypt.

Most of the deaths and injuries occurred in Cairo's eastern Matariyah district, an Islamist stronghold where police clashed with supporters of the outlawed Muslim Brotherhood group, according to CBC News. Security officials said nine protesters and one police officer died during the clashes in this region. 

Two people died when they attempted to plant an explosive device under a high voltage tower in the Nile Delta. The device exploded prematurely. Two other protesters died in Cairo and another in the Mediterranean port city of Alexandria. A roadside bomb exploded in an eastern Cairo district injuring two police officers and six more were injured in the clashes in Matariyah. 

Police arrested about 134 people across the country as they dispersed crowds, ABC Online reported. Police fired shotguns and tear gas at hundreds of protesters who attempted to march on the central Tahrir Square. The Tahrir Square was the center of the 2011 uprising that ousted former President Hosni Mubarak. 

Tensions had started building prior to the anniversary, ABC Online said. An explosion wounded four police officers and a civilian Friday, while on Saturday a female demonstrator died during a left-wing protest in Cairo after clashing with the police. 

Protesters accuse the new president, Abdel Fattah al-Sisi, of reinstating some aspects of Mubarak's reign. Sisi denies these allegations and said he is widely popular in the country and has much support in Egypt. 

The uprising in 2011 happened on Jan. 25, 2011. Hundreds of thousands of people took to the streets across Egypt for 18 days until Mubarak stepped down. Allegations of police abuses and corruption of the strongman's three decade rule sparked the revolt in 2011.