"For how long we will have to tolerate this bloodshed in our country?" a Kabul resident said Thursday, a day after a deadly vehicle bomb killed and wounded hundreds of people in the capital's highly secure area.

"I have lost my brother in the blast, and the government is constantly failing to provide us with security," he added.

More than 1,000 demonstrators took to the streets in Kabul on Thursday and Friday, many carrying pictures of bomb victims, chanting slogans against the leaders of the national unity government -  President Ashraf Ghani and Chief Executive Abdullah Abdullah.

Protesters demanded answers from the government over the perceived intelligence failure leading to the attack.

As a demonstration in the city turned violent, police fired into the crowd, killing at least three protesters, according to local media reports.

No militant group claimed responsibility for the Wednesday bombing, but the Taliban and self-styled "Islamic State" (IS) groups have staged large-scale attacks in Kabul in the past.

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After initial investigations, Afghan authorities said Pakistan-based militant Haqqani Network carried out the attack, and that the Pakistani military's Inter-Services Intelligence (ISI) security agency was also responsible. A source close to the Afghan presidential palace said that President Ghani had signed an order to execute 11 imprisoned Haqqani Network and Taliban convicts following the attack.

Apart from the Afghan government, a number of independent Afghanistan experts and Western officials have pointed to the ISI-Haqqani nexus.

Sediq Siddiqui, the spokesperson for Afghanistan's interior ministry, told media the role of Pakistan's ISI had been established in Kabul explosion. "We have nailed Pakistan's ISI role (in Kabul blast). Afghanistan expects Pakistan to crack down on Haqqani Network. The attack will surely impact ties between the two (Afghanistan, Pakistan) countries," Siddiqui said.

Rahmatullah Nabil, the former chief of Afghanistan's National Directorate of Security intelligence agency, alleges that Pakistan has been "playing a deadly game in Afghanistan."

"Pakistan wants to find new support for its proxy jihadists. It also wants to convey a message to the US that without Pakistan's help, Washington is going to fail in Afghanistan," Nabil told DW.

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Pakistan on Thursday dismissed the allegations that its intelligence agencies were behind Wednesday's truck attack. "We reject the baseless allegations. The accusatory approach is unhelpful towards efforts for peace," Foreign Office spokesperson Nafees Zakria said at a weekly news briefing in Islamabad.

Pakistan and the Haqqanis

It is not the first time that Afghan officials have accused Islamabad of giving Islamists logistical and military support to launch attacks on Afghan soil. Afghanistan and Western countries have long accused Pakistan of distinguishing between "good and bad jihadists" - the ones that attack Pakistani soldiers, and the ones that it allegedly uses as proxies in Afghanistan and India-administered Kashmir.

Pakistan continues to deny it is backing Haqqani Network, which is largely based in its Waziristan region close to the Afghan border. Pakistan no longer believes in separating the "good" and "bad" Taliban, a senior government official said in 2015.

Last year, President Ashraf Ghani's government blamed Haqqani Network for a major terrorist attack on the headquarters of an Afghan security agency in Kabul. The attack near the US embassy and government ministries killed at least 64 people and wounded over 300.

The attack infuriated the Afghan government to an extent that President Ghani had to say that his country "no longer expects Pakistan to bring the Taliban to the negotiating table" - a clear indication that the Afghan authorities no longer trust Islamabad in the fight against Islamic militants.

Mujahed Andarabi, the head of news for the Kabul-based 1TV, said the Wednesday bombing was part of a "big game" being played by the Taliban, Haqqani Network and some regional countries, including Pakistan. The Afghan government needs a clear-cut approach toward Pakistan, he underlined.

Andarabi says there is an international consensus against Pakistan, which is being isolated regionally and globally. Ghani's government should use this opportunity to make Afghanistan more independent, he stressed.

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Afghan expert Miagul Wasiq believes the success of the Afghan peace process largely depends on Pakistan's role. If Pakistan really wants to bring the Taliban into negotiations, it would be impossible for the militants to turn them down, he told DW.

"It is clear that the Taliban leaders are based in the Pakistani cities of Peshawar, Karachi and Quetta. Pakistan hasn't forced them to shun their activities and stop using its soil," said Wasiq. "If Pakistani officials stop backing them, I am sure the militants will have no option but to join the peace talks."

But Naufil Shahrukh, a researcher at the Islamabad-based Institute of Policy Studies (IPS), says that Pakistan has practically no influence over the Taliban leadership. "Such preconceived notions should be cleared before any meaningful initiative can take root," he told DW. "We must admit that the Taliban are still a potent force in Afghanistan. They control, and have public support, in several Afghan provinces."

History of mistrust

The ties between Afghanistan and Pakistan have never been worse. Apart from allegations and counter-allegations that the other country is backing armed militants, the two neighboring countries have been engaged in sporadic border clashes.

Amid worsening ties with Afghanistan, Pakistan announced in March it had started building a fence along the volatile Afghan-Pakistani border. Islamabad said the move was aimed at restricting the movement of Islamist militants that cross over the porous border and launch attacks on Pakistani soil.

In fact, there has been a long history of mistrust between the two nations.

"History has proven that Pakistan wants a weak government in Afghanistan so it can remain as the only mediator for the crisis in its neighborhood for the international community," Ahmad Zia Ferozpur, a lecturer at the Balkh University, told DW, adding that the only time Pakistan was happy with Afghanistan was during the Taliban regime.

"In 2001, Islamabad agreed to join the campaign against the Taliban due to international pressure but started a double game of supporting the Islamist insurgency and the international effort in Afghanistan simultaneously," Ferozpur underlined.

But he emphasized that Afghanistan's anger is directed against the Pakistani military and the ISI, not its people,

According to Sadaf Gheyasi, an Afghan journalist and activist, social media has played a big role in how the Afghans see Pakistan now. "The Afghan government has provided ample proof of Pakistani interference in Afghanistan through social media," she said.

But things can change now under President Ghani's government, believes Shukria Barakzai, an Afghan parliamentarian. "What we ask from Pakistan is not impossible: We want Islamabad to sign a transit agreement with Afghanistan and stop interfering in Afghanistan's security," she told DW. "Afghanistan has tried all options with Pakistan. If Pakistan does not change its policies, our last option will be to consult the United Nation's Security Council," she warned.

Additional reporting by Ahmad Hakimi and Masood Saifullah.