Four of police forces, including a policewoman, were killed during the bombing that hit Alexandria's St. Mark Cathedral on Sunday, interior ministry said in official statement. Two police officers, one policewoman and a police conscript of Alexandria police forces were bombed during their attempt to stop the bomber, who was armed was an explosive belt, from entering the Cathedral, where Coptic Patriarch, Pope Tawadros II was praying Palm Sunday's liturgy. "Security services, civil defense forces and bomb experts moved right away to the explosion sit to comb the area and secure it," the statement reads, referring that killed forces of police included Brigadier General Nagwa al-Naggar, Police Chief Emad el-Rakaiby, Police Chief Mohamed Refaat and police conscript Ahmed Ibrahim. A huge explosion hit Alexandria's St. Mark Cathedral on Sunday, leading to the killing of 13 persons and injury of 15 others, including 12 police officers. Coptic Patriarch, Pope Tawadros II was praying Palm Sunday's liturgy from Alexandria's cathedral. According to security sources, the bombing came as a result of planting a bomb near the cathedral's back door. It added that the explosion came minutes after Tawadros' departure from the cathedral heading to Tanta's St. George Church that witness similar explosion hour before. A number of ambulances transferred the injured to the hospitals to receive treatment, as the security forces take intensive measures in anticipation to any other potential attacks. On a televised statement, Secretary of Pope Tawadros said that a suicide bomber blew himself up before the church. According to medical sources, the bombing led to the killing of ten citizens and the injury of other 14.