CAIRO (Reuters) - Egyptian security forces shot dead 24 militants belonging to the country's Islamic State affiliate in central Sinai, 70 kilometres from the crash site of a Russian passenger plane the group claimed it brought down, security sources said on Monday.

Security sources said they killed the militants as they hid in a mountainous cave and that they arrested eight of them.

Sinai Province, Islamic State's Egypt branch, is active in North Sinai where two years ago it launched an insurgency and has since killed hundreds of soldiers and policemen. It is rarely active outside that area.

(Reporting by Ahmed Mohamed Hassan; Writing by Ahmed Aboulenein; Editing by Luke Baker)