At least 35 people were killed and 45 injured in a fire inside a church in the Egyptian city of Giza on Sunday, two security sources told Reuters.

An electrical fire broke out as 5,000 worshippers gathered for Mass at the Coptic Abu Sifin church in the Imbaba neighbourhood, the sources said.

The fire blocked an entrance to the church, causing a stampede, they said, adding that most of those killed were children.

Giza, Egypt's second-largest city, lies just across the Nile from Cairo. (Reuters)