Islamic State
An Islamic State or Isis fighter. [Representational Image]Reuters

Islamic State (ISIS) is now officially the richest terrorist group ever followed by Hamas in second place, according to Forbes Israel.

The Forbes Israel report noted that to finance their operations, terrorist groups often end up operating as criminal organisations, by taking up activities such as drug trafficking, robberies and extortion. Another means employed by terrorist organisations is raising money through charities, donations and, in some cases, government agencies, according to the report.

A terrorist organisation, also has a business model to finance its activities: from maintenance, salaries and trainings, to acquiring of weapons and vehicles. The richest terrorist organisation today – and in history – is the Islamic State.

According to Forbes, the Islamist terror group, also known by the acronyms ISIS or ISIL, has an annual income of $2 billion. Hamas comes in second, with a yearly revenue of $1 billion. Colombia's FARC is ranked third with a $600 million annual turnover, while Hezbollah is fourth with $500 million. Fifth on the Forbes list is the Taliban with $400 million, followed by Al-Qaida and its affiliates with $150 million; Pakistani-based Lashkar e-Taiba with $100 million; Somalia's Al-Shabaab with $100 million; Real IRA with $50 million; and, closing the top-ten list is Boko Haram, with a $25 million annual revenue.

                                Forbes Israel: Top 10 List of Richest Terrorist Organisations

1 ISIS (ISIS) $2 billion
2 Hamas $1billion
3 Revolutionary Armed Forces of Colombia – People's Army or FARC $600 million
4 Hezbollah $500 million
5 Taliban $400 million
6 Al-Qaeda and affiliates $150 million
7 Lashkar e-Taiba $100 million
8 Al-Shabaab $70 million
9 Real IRA $50 million
10 Boko Haram $25 million

 According to the estimates by the U.S. Treasury, ISIS earns $1 million a day by selling crude oil from captured oil-fields in Syria and Iraq in the black market.

Forbes Israel, however, states the daily revenue figure is around $3 million. The money flow enables ISIS to smoothly carry forward its operations in the Middle East, recruit foreign fighters and train them.

On Hamas, the Forbes report says that the group's takeover of Gaza in 2007 was the point when it entered "the big league."