"The prosecutor general orders the detention of former President Hosni Mubarak and his sons Gamal and Alaa for 15 days pending investigation after the prosecutor general presented them with the current state of its ongoing investigations," said a post on the prosecutor general's Facebook page on Wednesday.

The announcement came a day after Mr Mubarak had been admitted to hospital with heart problems, although reports indicated that he was well enough to undergo questioning.

Mr Mubarak, 82, is in hospital after reportedly suffering heart problems. His detention order will be in place for 15 days, state TV reported.

His sons Alaa and Gamal have also been detained amid allegations of corruption and violence, police say.

Mr Mubarak stood down in February after a popular uprising against his rule.

Since then, tens of thousands of protesters have staged weekly Friday protests in Cairo's Tahrir Square, demanding that he stand trial.

About 800 people are thought to have been killed during the protests, as police opened fire and cracked down on the crowds.

There are also widespread allegations of corruption and abuse of power under Mr Mubarak's 30-year rule.