Egypt's interior ministry on Thursday identified the suicide bomber in the church bombing in the city of Tanta as Mamdouh Amin Mohamed Baghdadi, a resident of Qena, south of Cairo.
At least 45 people, as well as the bombers, were killed in attacks on a cathedral in Alexandria and the church in Tanta in the Nile Delta on Palm Sunday, April 9. So-called Islamic State (IS) group claimed responsibility for the attacks.
A ministry statement said Baghdadi was born in 1977 and was one of 19 suspected militants believed to belong to a cell behind a December suicide bombing of Cairo's main Coptic cathedral, another attack claimed by Islamic State.
The statement said the authorities had arrested 3 of the 19 suspected militants in the cell.
Egypt's government imposed a three-month state of emergency in the wake of the Palm Sunday attacks.
Religious minorities are increasingly targeted by Sunni Islamist militants, posing a challenge to President Abdel Fattah el-Sissi, who has pledged to protect them as part of his campaign against extremism.
IS has waged a low-level war against soldiers and police in Egypt's Sinai Peninsula for years but it is increasingly targeting Christians and broadening its reach into Egypt's mainland.