CAIRO: At least 55 people were injured on Friday when a passenger train derailed south of Egypt's capital Cairo, an assistant to the health minister told state television.

"Most of the injuries are minor," Ahmed Mohei said.

Three carriages on a train headed to the southern province of Qena went off-track, state news agency MENA said citing a transport ministry statement.

Public Prosecutor Nabil Sadek ordered a investigation into the accident, the cause of which remains unknown.

Egyptians have long complained that governments have failed to enforce safety on the antiquated rail network.