Image copyright EPA

In the Afghan capital, Kabul, there's still widespread shock and anger at the brutal militant attack last week on the city's main military hospital.

The authorities have acted swiftly, sacking the deputy interior minister and arresting 24 hospital and military officials, including an army general.

But for many Kabul residents it feels too little, too late.

A local man interviewed on the street this week by state TV spoke for many.

"If this government can't fulfil its responsibilities, someone else needs to take over," he said.

"People have had enough of this situation."

Image copyright Reuters Image caption Officials put the death toll at 50, with 31 injured - though these figures are disputed

The 400-bed Sardar Daud Khan hospital is set in extensive grounds in Kabul's diplomatic district, not far from the US embassy, Nato headquarters and the Afghan state television building.

People are demanding to know how such a supposedly secure defence ministry facility could be so vulnerable to attack.

The issue has been furiously debated in parliament and continues to be a key subject of conversation on social media.

Image copyright EPA Image caption Smoke billowing out during the attack at Sardar Daud Khan Hospital

At a hastily arranged press conference this week, defence ministry officials presented their initial findings.

Contradictions

But their version appeared to contradict the accounts of some eyewitnesses and Afghan politicians, and many key questions remain unanswered.

One of the biggest is how the attackers were able to get into what was supposed to be a heavily-guarded compound.

A medical technician who has worked at the hospital for almost a decade told the BBC that security was always very tight.

"Everyone entering the building, including staff, is frisked and their bags are checked," she said.

So did the attackers have help from inside?

Image copyright AP Image caption Deputy Defence Minister Gen Helaludin Helal briefed reporters about the attack on Wednesday

The defence ministry says five people were involved and that they entered the compound in a car with fake number plates.

One blew himself up at the hospital gates and the others ran inside.

But eyewitnesses, including one who spoke to the BBC, reported hearing gunfire in the hospital corridors at exactly the same time as the blast at the entrance - suggesting at least some of the group could have already been inside.

Disguised as doctors

One eyewitness who spent three hours hiding inside the cardiology department told the BBC that a colleague had seen men in white coats opening fire on people in the corridor.

Ahmad Nesar Hares, a member of the Afghan Senate Committee investigating the attack, told a heated Senate debate this week that according to his information as many as 17 militants were involved and that they had been let in by "an enemy who worked in the hospital for three months".

Media playback is unsupported on your device Media caption Special forces were involved in an operation to stop the hospital attackers

"He transferred weapons, guns and ammunition to the hospital and nobody caught him," the senator said.

In a similar vein, some media reports have quoted hospital staff as saying two of the people involved in the attack were interns who had been working there for several months.

The defence ministry says it has no evidence so far that the attackers were helped by medical staff but investigations are ongoing.

Image copyright AFP Image caption The attackers were eventually killed after several hours of fighting

One thing that is not disputed is the brutal nature of the attack.

The defence ministry said the attackers were armed with AK47s, grenades and military issue knives. They also confirmed reports circulating locally that patients had been shot and stabbed to death in their hospital beds.

The exact death toll continues to be disputed.

The defence ministry revised its official figure up to "around 50" with 31 people injured. However, some hospital workers quoted in local media reports insist it was much higher.

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The eyewitness who spoke to the BBC said the corridor outside her ward had been full of people when the attack started.

She described watching a scene of horror unfold with her patients, who were finally rescued by Afghan commandoes.

"There were bodies lying everywhere," she said. "Patients, doctors, people I knew and worked with. It was terrible. I will never ever forget it."

It's still not clear who exactly carried out the attack.

The Afghan defence ministry says that both Afghan and foreign nationals were involved, but has dismissed social media speculation about their identity.

Image copyright AFP/Getty Image caption It is still not clear who was behind the attack

While the violence was still going on, so-called Islamic State (IS) issued a statement via its Amaq news agency claiming responsibility.

However Afghan security experts have questioned whether a group still thought to be relatively small in Afghanistan could be capable of planning and carrying out such a large scale operation.

Afghan fighters who have declared allegiance to IS are thought to control just a handful of villages in eastern Nangarhar province.

Some eyewitnesses have told local media that the attackers were shouting slogans in support of the Taliban.

One patient who spoke to the BBC said he saw men he described as "Taliban" shouting Allahu Akbar ("God is greatest") and throwing grenades in the corridor.

It's been widely reported that the wards containing Taliban patients were left untouched.

The defence ministry confirmed that injured Taliban fighters were being treated in the hospital but said they were in locked wards with barred windows, and that they were not involved in the violence.

The ministry has asked for patience as it continues to investigate what it said was "a complex case" and has pledged to share more information in the coming weeks.

Syed Anwar and Jenny Norton contributed to this report.