Nigeria’s President, Muhammadu Buhari, has vowed to crack down on groups responsible for attacks on oil pipelines, which have contributed to a fuel shortage in the country, Newsweek reported. Buhari made the comments during a state visit to China in April, where he has been meeting with Chinese President, Xi Jinping, to secure support for infrastructure projects.

As Reuters wrote, pipeline attacks and violence have been on the rise in the southern swampland since authorities issued an arrest warrant in January for a former militant leader on corruption charges. “We will deal with them the way we dealt with Boko Haram,” Buhari said, referring to  militants who have been waging an insurgency to set up an Islamic state in the north.

The army has recaptured much of the territory that Boko Haram had held since Buhari took office in May 2015, though the group still stages suicide bombings. “I hope this message will reach the vandals and saboteurs who are blowing up pipelines and installations,” the Nigerian President added.