Eight months after a coalition of nearly 10,000 troops embarked on a mission to free Mosul from the Islamic State group (also known as ISIS), Iraqi Prime Minister Haider Al-Abadi declared Sunday the terror group was wiped out from the city.

"Al-Abadi said the battle is settled and the remaining pockets of ISIS are encircled in the last inches of the city. It is a matter of time before we declare to our people the great victory,” Abadi’s media office said in a statement. A day after al-Habadi arrived in the city to congratulate the forces, the troops Monday pushed to retake the last patch of ground in Old City, west of Tigris river, multiple reports said.

The fall of Mosul comes three years after ISIS leader Abu Bakr al-Baghdadi declared himself the leader of the caliphate from Al-Noori mosque in Mosul. But the 12th century mosque was reportedly destroyed by ISIS fighters in June, when they were approached by the U.S.-backed coalition forces. ISIS, however, blamed U.S. strikes for destroying the mosque, according to some reports.

Millions of people have been displaced ever since the offensive to retake Mosul was launched in October last year. The city is considered one of the main entry points for foreign fighters to enter the country. Apart from its strategic location, Mosul’s proximity to oil fields is also a reason why the terrorist group’s retreat from the city may give a boost to the country’s economy.

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Amid the raging battle in the city over the past few months, ISIS lost thousands of troops and several of its leaders. A top Iraqi commander was quoted as saying in a report about 1,000 terrorists of the group have been killed in more than two months. Scores of car-bombs and rockets of the group were destroyed during the fighting, Police Chief Lieutenant General Raed Jawdat said in a statement.

One of Baghdadi’s close aide, who was also the group’s currency leader, was reportedly assassinated July 2 in a targeted raid. The assassinated leader was tasked with designing the group’s golden currency for the group’s treasury department. It is also not confirmed if Baghdadi is alive despite claims about his death by Russia and Iran. The claims have been questioned by the U.S. in the past.

Meanwhile, despite the defeat it is still not clear whether the ISIS threat is over in Iraq and Syria.

A report released June 28 stressed that ISIS continued to pose a threat even after several cities in Iraq and Syria were freed from the group. Nearly 1,500 attacks in 16 cities in Iraq and Syria were carried out by ISIS even after these cities were liberated, a report by the Combating Terrorism Center at West Point said. “Cities in Iraq appear to experience more post-liberation violence than do cities in Syria. There is tremendous diversity in the data, as six cities experienced fewer than two attacks per 30 days,” the report said.

According to the study, pushing the Islamic State out as the formal governing party in a territory is not a sufficient development when it comes to ending the group’s ability to enact violence against individuals in Iraq and Syria. Governments need to ensure efforts to restore the security, governance and economies in such territories, the study pointed out.

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Often labeled as the richest terrorist organization, ISIS, however, is grappling with a dramatic decline in its revenues, revealed a study by the International Centre for the Study of Radicalisation and Political Violence (ICSR) at King’s College, London. “In the years since 2014, Islamic State’s annual revenue has more than halved: from up to $1.9b in 2014 to $870m in 2016. There are no signs yet that the group has created significant new funding streams that would make up for recent losses,” the study underlined. The terror group relies on three primary sources for revenue: taxes and fees, oil and looting, the research pointed out.

Depleting funds notwithstanding, attacks by ISIS in Western countries may increase in the near future because the group has already prepared its followers for the loss of territory and resources, another report by IHS Markit underlined. "Territorial losses are driving the Islamic State to intensify its campaign of terrorist attacks abroad to compensate," said the report.

“Efforts by Western governments to confront Islamists are likely to have the same effect. Terrorism risks from the Islamist groups are therefore likely to increase before they decrease,” Firas Modad, senior Middle East analyst at IHS Markit, said. The analysis also said the group had lost more than 60 percent of its territory and 80 percent of its revenue. “The Islamic State’s average monthly revenue has fallen dramatically from $81 million in Q2 2015 to $16 million in Q2 2017, a reduction of 80 percent,” it said.