Security officials and investigators inspect the scene of a bomb blast in Giza al-Haram Street on the outskirts of Cairo, Egypt December 9, 2016.

One man was killed and three others injured in an explosion in the Cairo suburb of Maadi, the Interior Ministry said in a statement on Friday.

The man who was killed, a building guard who was cleaning the property’s garden, found “an unidentified metallic object.” Upon handling it, it exploded, resulting in his death and the injury of his wife and two children by shrapnel, the statement said.

The injured have been moved to the hospital for treatment and the area had been cordoned off and is being combed by security forces, it added.

There was no immediate claim of responsibility.

The government is taking on militants in the Sinai Peninsula, where militants loyal to Islamic State are based, and extremist groups elsewhere in the country who generally target security forces.