Militants on Monday raided a military academy in the Afghan capital Kabul, killing 11 soldiers and injuring 15 others in what was the fourth major attack in just nine days. The defence ministry said just before dawn, five gunmen armed with rocket-propelled grenades and automatic rifles attacked an army outpost near the well-defended Marshal Fahim military academy on the city’s outskirts before they were subdued. Islamic State claimed responsibility for the attack. “The Afghan National Army is the country’s defence force and makes sacrifices for the security and well-being of the people,” the ministry said. Security officials at the scene said the gunmen had used a ladder to get over a wall into the post. It came two days after an ambulance bomb in the city centre killed more than 100 people and just over a week after another attack on the Hotel Intercontinental, also in Kabul, killed more than 20. Both of those attacks were claimed by the Taliban. Islamic State claimed an assault on the office of aid group Save the Children in the eastern city of Jalalabad on Wednesday in which six people were killed. In October, a suicide attacker rammed a car full of explosives into a bus carrying cadets from the academy, known as the Defence University, killing 15. While militants claiming allegiance to Islamic State operate in mountains in the eastern province of Nangarhar, little is known about the group and many analysts question whether they are solely responsible for the attacks they have claimed in Kabul and elsewhere. The recent string of attacks have put pressure on President Ashraf Ghani and his US allies, who have expressed growing confidence that a new, more aggressive military strategy has succeeded in driving Taliban insurgents back from major provincial centres. The United States has stepped up its assistance to Afghan security forces and its air strikes against the Taliban and other militant groups, aiming to break a stalemate and force the insurgents to the negotiating table. Afghan capital on edge after ambulance bomb kills 103 However, the Taliban have dismissed suggestions they have been weakened and said Saturday’s bombing was a message to President Donald Trump. “The Islamic Emirate has a clear message for Trump and his hand kissers, that if you go ahead with a policy of aggression and speak from the barrel of a gun, don’t expect Afghans to grow flowers in response,” Taliban spokesman Zabihullah Mujahid said in a statement, using the term the Islamist militants use to describe themselves. This week’s surge of violence is unlikely to sway the US strategy, or breathe life into stalled efforts to get peace talks going. The US military and the Afghan government say big attacks on civilians are evidence that the militants are being squeezed in the countryside. Trump condemned the Saturday attack, saying it “renews our resolve and that of our Afghan partners”. “We will not allow the Taliban to win!” he said on Twitter on Sunday. But Ghani, embroiled in confrontation with provincial power brokers defying central rule, faces anger from an increasingly frustrated population, who want him to set aside political divisions and focus on security. “People think the government is working very badly, that the security agencies think about themselves and don’t care, and the international coalition just wants to fight with air strikes and doesn’t have any good intelligence,” said Najib Mahmood, political science professor at Kabul University. Saturday’s blast in one of the most heavily protected parts of the city, close to foreign embassies and government buildings, was the worst in the Afghan capital since a truck bomb near the German embassy killed 150 people in May last year. The May blast triggered bloody anti-government protests but there has been no sign of any such agitation this week. The United States and Afghanistan have accused Pakistan of helping the Taliban in a bid to undermine old rival India’s growing influence in Afghanistan. Pakistan, which denies accusations it fosters the Afghan war, condemned the attack and called for “concerted efforts and effective cooperation” to tackle militancy. A few hours after Monday’s attack, Indonesian President Joko Widodo arrived in Kabul. Indonesia has the world’s biggest Muslim population, and Widodo has proposed its Islamic scholars could help promote Afghan peace.