Militants opened fire at a bus in northern Pakistan, killing nine people including two soldiers, and injuring over 20 others, local police said.

The attack happened Saturday night on the Karakoram Highway in northern Gilgit Baltistan region, police officer Azmat Shah said. The highway connects Pakistan with China and also passes through the Khyber Pakhtunkhwa province which has been a hotbed of terrorism in the past due to the presence of Pakistani Taliban and other militant groups in the area.

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The bus was carrying passengers from Gilgit to the city of Rawalpindi when it was shot at, causing the driver to lose control and crash into a truck, which in turn caught fire. Both drivers were killed on site.

At least 26 people were injured — including a local Islamic cleric, Mufti Sher Zaman — and transferred to local hospitals, as police helped reroute traffic in the area after condoning off the site, officials said.

The home minister of Gilgit Baltistan, Shams Lone, called the incident an “act of terrorism.”

Pakistan’s interim prime Minister, Anwaar-ul-Haq Kakar, in a statement issued by his office, condemned the attack, saying that “anti-state elements would not be allowed to sabotage the peace of Gilgit Baltistan,” and vowed to continue fighting “against terrorists.”

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A special investigation team was formed to look into the attack and apprehend those behind it, according to the chief minister of Gilgit Baltistan, Gulbar Khan.

No one has immediately claimed responsibility for the attack.

In a statement Sunday, Muhammad Khorasani, a spokesman for the Pakistani Taliban, also known as Tehreek-e-Taliban Pakistan or TTP, denied his group being behind the shooting.

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The TTP is a separate group but allied with the Afghan Taliban, who seized power in Afghanistan in August 2021 as U.S. and NATO troops were in the final stages of their pullout from the country. It has waged an insurgency in Pakistan over the past 15 years.