The Egyptian government has referred 48 people to its military courts on the charge of suspected involvement in three church bombing claimed by ISIS.

Egypt's public prosecutor's office said on Friday that of the 48 suspects, 31 are in custody, with 17 still at large, according to Al Jazeera.

Public prosecutor Nabil Sadek said that some of the accused were leaders within ISIS, and had formed terrorist cells in Cairo on Qena, southern Egypt, to plan and execute the church bombings.

ISIS previously claimed responsibility for three suicide bombings on Coptic churches in the past six months.

In December, the jihadists claimed responsibility for a Cairo Coptic church bombing that killed 27.

This year ISIS vocally incited violence against the Coptic community, forcing hundreds to flee their homes in northern Egypt in February. Palm Sunday bombings on two Egyptian churches in Tanta and Alexandria – the seat of the Coptic Pope – killed at least 45 and injured over 100.

The suspected terrorists are believed to have undergone training at ISIS camps in Libya and Syria. They are also accused of killing eight policemen and wounding three in a January attack.

After April's bombings, Egypt's president Abdel Fattah al-Sisi placed the country in a three-month state of national emergency.

Earlier this month, ISIS' leader in Egypt warned Muslims to stay away from Christian gatherings, as well as government facilities, warning of future attacks on what he called 'legitimate targets' to come.