Egypt’s top prosecutor ordered on Tuesday the detention of 23 defendants pending investigations into a deadly derailment of a passenger train en route to the Nile Delta city of Mansoura, which killed 23 people and injured dozens.

According to a statement, prosecutor general Hamada Al-Sawy ordered the detention of the train driver, assistant, a railway maintenance observer at the crash site, the head of refurbishment of the area, and others, including workers of Cairo’s main train station.

The prosecution ordered the release of two people, the head of infrastructure maintenance and the head of the central department for units maintenance, after they paid a posted bail, the statement said. Arrest warrants were issued for others.

The fatal derailment took place on Sunday when four carriages had run off the track near Toukh city in Qalioubiya in the Nile Delta while en route from Cairo, leaving 23 people dead and 139 injured according to an updated toll from the prosecution on Tuesday.

Earlier, the health ministry put the toll at 11 killed and 98 injured.

Some of the defendants were charged with the wrongful death of 23 of the train’s passengers due to negligence, the statement said.

They were charged of involuntarily causing an accident to a public transportation means, which endangered people's lives and resulted in the death and injuries of some, the statement said, with others charged with negligence over the maintenance and use of public funds.

The prosecution also charged several of the defendants of forging official documents, it said.

It determined an initial scenario for the accident, which it said occurred after several carriages from the train 949 fell off the track with some of wheelsets disconnected, leading to their derailment.

The prosecution said the arrests and the initial scenario came after its inspection of the crash site and testimonies by 29 of National Railways Authority (NRA) officials and 104 of the injured.

It had also formed a technical committee comprising the armed forces engineering authority, the military technical academy’s advisory bureau and a member of the Administration Control Authority to inspect the train and its safety equipment and the validity of railway at the crash site.

The top prosecutor has also summoned the now ex-chairman of the National Railways Authority Ashraf Raslan, who was dismissed by Transport Minister Kamel Al-Wazir earlier on Tuesday over the accident.

The newly appointed NRA chairman Mostafa Abdel-Latif was also summoned by the prosecutor-general, according to the statement.

Sunday's deadly derailment comes nearly a week after a train crash in Sharqiya injured 14 people.

The recent train accidents come less than a month after two trains collided in Upper Egypt’s Sohag, killing 20 people and injuring 199 others.

Investigations into last month's deadly train collision revealed human error and negligence by railway employees.

Egypt's railway system has had a poor safety record for decades, with deadly collisions and accidents that are often blamed on poor maintenance and management.

Officials have repeatedly stressed that billions of pounds and several years that are needed to upgrade the country’s railway network to provide better service to the public and prevent deadly accidents.