In April 2016, in Basilan, Islamic militants gathered to mount an attack on the Armed Forces of the Philippines. The attack they launched killed 18 soldiers and injured more than 50 others.

The small island of Basilan, a member of the Sulu Archipelago that stretches southwest off Mindanao in the southern Philippines, had long been the origin of many of Abu Sayyaf’s top leaders. But the assault entrenched Basilan’s reputation as the stronghold of Abu Sayyaf, a group composed of multiple loose networks, some of which have declared allegiance to the Islamic State of Iraq and Syria (ISIS).

But in mid-2016 the various forms of violence that once beset Basilan began to subside, and since then there’s been a relative outbreak of peace. With the efforts to reconstruct Marawi following the five-month siege by ISIS-inspired groups, it’s prudent to investigate the circumstances that led to Basilan’s stabilisation and whether it be can replicated in other parts of the Philippines that are struggling with endemic violence.

Abu Sayyaf had exploited the insurgent violence, pervasive criminality and constant feuding between familial clans to entrench itself in the politics of Basilan. Using a cocktail of violent threats and political inducements, the group convinced numerous local governments around Basilan to provide it with sanctuary. Contrary to popular perception, Abu Sayyaf didn’t prey on the absence of government in Basilan; instead, it corrupted the government from the inside.

Basilan’s violence began to recede after Jim Hataman became the new provincial governor following the May 2016 elections. He prioritised quelling violence, informing mayors and village heads from across Basilan that they would be held accountable if Abu Sayyaf was found to be operating in their jurisdictions.

This strategy had been tried before, but the Philippine electoral system confers only limited power on provincial governors to control their mayors. Those mayors, while technically reporting to the governors, are selected by voters in local elections. Previously, mayors were often more scared to defy the demands of Abu Sayyaf than the instructions of their toothless governors.

But circumstances had bestowed on Hataman an unusual amount of political power. His ally and brother, Mujiv, was the regional governor, which gave their family unmatched power over the government budgets on which mayors relied. The family had reached a détente to end their longstanding rivalry with the Akbar clan, allowing Hataman to govern without being dogged by constant political infighting. Rightly or wrongly, many local mayors believed that martial law provided Hataman with the power to summarily fire them, rendering them more likely to obey his directions.

With his newfound political power, Hataman hatched a plan to rid Basilan of Abu Sayyaf. It focused on depriving the group of the sanctuary and resources that had until then been provided by Basilan’s community leaders.

Few local leaders had ideological sympathy for Abu Sayyaf’s extremist views. But in the remote regions of Basilan, they were allowing the group to operate—mostly because they were afraid that if they refused they would be its next victims. Making these leaders feel sufficiently safe to defy Abu Sayyaf’s demands was the critical first step for the Hataman plan.

Basilan’s rugged terrain and modest resources made it impracticable to provide every local leader with round-the-clock government security. So Hataman decided on an alternative: allow them to develop their own security teams. Private militias had been common in Basilan. They were a source of prestige in a culture that values warriors and armed strength and in a system in which weapons are used to win elections.

Hataman believed that these local militias, which had long being a source of violence, could become a tool for stability. By conferring on them the status of ‘peacekeeping action teams’, he made it possible for them to be trained by the Philippine armed forces and police. With this change, local leaders felt increasingly safe to defy Abu Sayyaf’s demands, secure in the knowledge that they would be protected by their own more legitimate, more capable militias.

With Abu Sayyaf already on the back foot, and many of its leaders moving to mainland Mindanao, Hataman capitalised by mobilising Basilan’s society. Muslim religious leaders, who had been scared of violent reprisals, now felt safe enough to publicly denounce Abu Sayyaf. The business sector, long crippled by pervasive extortion, threw its support behind the Hataman plan.

With violence decreasing, the provincial government was able to expand public services into the remote regions that had once been Abu Sayyaf’s stronghold. The government’s action also signalled that it was committed to and capable of providing services to the population, which bolstered its legitimacy.

Nothing guarantees that the drop in violence in Basilan will continue. On the contrary: the concentration of power will dissipate and martial law will hopefully end. But Basilan’s stabilisation gives insights into how to reduce the levels of violence in other parts of Mindanao.

Extremist groups grow strong when they infiltrate and co-opt local governments and leaders. Convincing those leaders to side with the forces of peace rather than violence is essential. In Basilan, this didn’t involve changing their ideology because few supported the extremist ideas of Abu Sayyaf.

Some felt it was in their political interests to maintain cordial relations with the group, and many gave it sanctuary simply because they were too scared to refuse. In short, ridding Basilan of Abu Sayyaf wasn’t about changing the ideology of local leaders as much as changing their incentives.

Basilan still suffers from far too much violence, and creating a more permanent peace is a generational challenge. Reconstructing the infrastructure and social fabric of Marawi is a similar challenge. But Basilan’s recent stabilisation demonstrates that provincial governments endowed with sufficient political power and sustained political commitment can, at least temporarily, reduce violence.