Customers of Commercial Bank of Ethiopia have capitalised on a “system glitch” to withdraw amounts that were more than what is actually in their bank accounts.

According to the BBC, over $40 million (£31m) had already been either withdrawn or transferred to other banks before the bank could freeze further transactions hours later.

Speaking at a press conference on Monday in Addis Ababa, the bank’s president, Abe Sano, alleged that most of the money was withdrawn by university students after reports of the glitch spread on Saturday through messaging apps and phone calls.

Failing to confirm the amount of money withdrawn, Mr Sano revealed that over 490,000 “unhealthy and illegal” banking transactions were made and processed but said the loss recorded was small compared to the bank’s total assets.

He assured customers of the safety of their monies, confirming that “there have been attempted cyber attacks, but the bank’s cyber security was not compromised.”

He said the glitch happened during their “maintenance and inspection activities” to improve their banking system and was caused by a “missing code,” prompting them to suspend their service to prevent more losses.

The bank’s president, however, stated that an investigation had been launched because they had reported to the authorities customers who had made high transactions.

He also called on customers to return monies that did not belong to them, promising they would not be charged with a criminal offence.

Ethiopia’s biggest commercial bank is now trying to recover the huge amount of money customers withdrew after the glitch.

A student in Western Ethiopia told the BBC that people had formed long queues at campus ATMs and were withdrawing money before police officers arrived to stop them.

The bank holds the accounts of over 38 million people.