Pakistan's prime minister has blamed India after five people - including at least three children - were killed when a suicide car bomber targeted an army school bus.
The attack in Khuzdar, in the southwestern region of Balochistan, took place while the bus was carrying around 40 children to school.
The incident also left 38 other people injured, with several children in critical condition, officials said.
Prime Minister Shehbaz Sharif directly blamed India for Wednesday morning's attack without providing any evidence.
He said: "The attack on a school bus by terrorists backed by India is clear proof of their hostility toward education in Balochistan."
Pakistan's military said the bombing was "yet another cowardly and ghastly attack" and alleged it had been planned by India and carried out by "its proxies in Balochistan".
Interior minister Mohsin Naqvi strongly condemned the attack and expressed deep sorrow over the children's deaths.
He called the perpetrators "beasts" who deserve no leniency, calling the attack an act of "sheer barbarism by targeting innocent children".
India's foreign ministry said it "rejects the baseless allegations" made by Pakistan.
No group has yet claimed responsibility for the attack, but suspicion is likely to fall on ethnic separatists.
The attack comes days after a car bombing killed four people near a market in Qillah Abdullah, a city in Balochistan bordering Afghanistan.
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Balochistan has been the scene of a long-running insurgency, with an array of separatist groups staging attacks.
They include the outlawed Balochistan Liberation Army (BLA), designated as a terrorist organisation by the US in 2019 and which Pakistan claims has the backing of India.
Earlier this week, the BLA vowed more attacks on the "Pakistani army and its collaborators" and says it wants to "lay the foundation for a peaceful, prosperous and independent Balochistan".
Tensions have increased between India and Pakistan amid a cross-border escalation over the disputed Himalayan region of Kashmir, with the nuclear-armed neighbours agreeing on what observers say is a "fragile" ceasefire on 10 May.
(c) Sky News 2025: Pakistan's PM Shehbaz Sharif blames India after school bus attack leaves five dead
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