Two days after al-Shabab militants killed almost 150 people in the Kenyan city of Garissa, Kenyan President Uhuru Kenyatta pledged the group would not create an Islamist caliphate in his country. His televised speech Saturday came just hours after the terrorist group threatened further bloodshed.

“We will fight terrorism to the end,” Kenyatta said, according to the Associated Press. “I guarantee that my administration shall respond in the fiercest way possible.”

U.S. President Barack Obama pledged his support for the Kenyan government in fighting extremism, both in a public statement Friday and in a phone call Saturday.

“I know that the people of Garissa and all of Kenya will grieve, but their determination to achieve a better and more secure future will not be deterred,” Obama said in his public statement. He also solidified his commitment to attend an entrepreneurship summit in Kenya in July. It will be his first trip to the country during his presidency.

“We will stand hand-in-hand with the Kenyan government and people against the scourge of terrorism and in their efforts to bring communities together,” the U.S. president said. “Even at this difficult hour, the Kenyan people should know they have an unwavering friend and ally in the United States of America.”

In his televised speech, Kenyatta promised to “do everything to defend our way of life,” Reuters reported. He called on his country’s Muslim community to help fight against radicalization, warning that “the planners and financiers of this brutality are deeply embedded in our communities.”

Shortly before Kenyatta’s speech, al-Shabab released a statement promising that “Kenyan cities will run red with blood” and that “no amount of precaution or safety measure will be able to guarantee your safety, thwart another attack or prevent another bloodbath.”

The U.S. classified al-Shabab as a Foreign Terrorist Organization (FTO) in 2008, and it has played major roles in offensives against the group. The group’s leader, Ahmed Abdi Godane, was killed by a U.S. airstrike in September 2014, and the Pentagon confirmed last month one of its drones had killed Adnan Garar, the senior member who helped plan the attack on the Westgate shopping mall in Nairobi in 2013.

Al-Shabab is a militant group based in Somalia, but it has increasingly been expanding its reach beyond that country’s borders in an attempt to incite a global jihadist movement. Early Thursday, masked members stormed stormed Garissa University College, about 120 miles from the Somali border, and killed 148 people in the most deadly attack in Kenya in 17 years.

Before the attack in Garissa, critics and whistleblowers claimed that widespread government corruption had “opened the door to al-Shabab in Kenya.” Now, many citizens are echoing this sentiment, feeling the government didn’t do enough to protect the school despite warnings of an attack days before.

“The people were trapped here for 13 hours: Where was the government? They failed to protect their people,” a local high-school student told Time. “We don’t feel safe here, and the government isn’t doing anything to protect us.”