Gunmen abducted the 12-year-old grandniece of the late Egyptian leader Anwar Sadat but released her nearly 24 hours later for 5 million Egyptian pounds (about US$840,000) in ransom, security officials said Monday.

The girl was kidnapped on her way to school Sunday morning in the upscale Cairo suburb of Heliopolis, the officials said, speaking on condition of anonymity because they were not authorized to speak to the media.

They said the kidnappers were in two cars and drove the girl through three Nile Delta provinces north of the Egyptian capital before they released her on the desert road from Cairo to the Mediterranean city of Alexandria.

She was being driven to school in a family car when one of the gunmen intercepted them and forced his way into the girl's vehicle. The kidnappers later beat the driver and forced the girl into one of their cars.

Sadat was assassinated in 1981. The girl's father is Sadat's nephew, businessman Effat Sadat.