CAIRO — A homemade bomb placed in a government construction site on the outskirts of Cairo exploded Saturday, killing a girl and wounding her mother, an Egyptian security official said.

The official said assailants placed the device in a government telecommunication building under construction in 6 October district. The girl’s mother, who is the wife of the building’s guard, was wounded in the explosion.

The governor of Giza, which includes 6 October, told the private CBC channel that the explosion damaged a mobile communication tower, cutting off access for 800 clients.

In a separate incident, gunmen shot and killed two civilians late Friday in the town of el-Arish in the northern part of the Sinai Peninsula. A security official said the assailants opened fire outside a police officer’s home as he was escorting two repairmen outside the front door. The police officer was unharmed.

All officials spoke on condition of anonymity because they were not authorized to brief reporters.

Egypt has seen a series of attacks mainly targeting security forces since the ouster of Islamist ex-president Mohammed Morsi last July. The Foreign Ministry says nearly 250 police have been killed in attacks since security forces dispersed a mass sit-in by Morsi supporters last August.

On Wednesday, four small explosions went off in subway stations and outside a court building in Cairo, wounding three people and marking the first attacks since the election of President Abdel-Fattah el-Sissi, the former army chief who led last year’s ouster of Morsi.

Copyright 2014 The Associated Press.