Hasm, which has claimed responsibility for several previous attacks targeting mainly — but not exclusively — police checkpoints in recent years, denied its involvement in the latest attack, the deadliest in Cairo in over two years. The majority of Islamist militant attacks have taken place in the northern Sinai Peninsula where the military has been battling an Islamic State-affiliated insurgency since the overthrow of Muslim Brotherhood President Mohammed Morsi in July 2013. Confirming that the attack was "a terrorist incident," President Abdel Fattah al-Sisi offered his condolences to the Egyptian people and the families of the victims in a message published on his official Facebook page. Sisi also reiterated his oft-repeated vow to root out the terrorists: "Egypt is determined to defeat brutal terrorism," he wrote.

In a statement published on its official Facebook page Aug. 5, the Interior Ministry said a speeding car, which was reported stolen some months earlier in the Nile Delta province of Menoufia and carrying explosives that would have been used in a prospective terrorist attack, collided with three cars heading in the opposite direction, causing it to detonate its charge. While there was no mention of the intended target of the potential attack, the Interior Ministry's statement accused Hasm, a militant group purportedly linked to the outlawed Muslim Brotherhood, of carrying out the attack and said investigations were underway to identify and hunt down the perpetrators and bring them to justice.

Security cameras captured images of a car traveling in the wrong direction on a one-way street running alongside the Nile River in the area outside the NCI minutes before the eruption. The video shows a massive fire breaking out , presumably the vehicle itself bursting into flames. Images of patients, including sick children, being evacuated from the hospital quickly circulated on social media , evoking shock and dismay among Egyptians.

Initial reports by the pro-government Youm7 and other Egyptian news sites said an oxygen tank exploded inside the institute and firefighters were heading to the hospital to extinguish the blaze. But Cairo University quickly contradicted the news accounts, saying the explosion was caused by a car collision outside the hospital, causing extensive damage to the facade of the building.

Egyptians are reeling from the shock of a deadly blast that rocked the central Cairo neighborhood of Manial just before midnight Aug. 5. The explosion that occurred outside the Cairo University-affiliated National Cancer Institute (NCI), an oncology hospital and research center, left 22 people dead and dozens injured. The death toll may rise further as some of those injured are in critical condition.

But many opposition activists were unconvinced. Some responded with skepticism to Sisi's comment, pointing the finger at authorities instead for what they called "a fake terrorist incident."

"Just look at the timing of the explosion, coming after Egypt hosted the African Cup Football Tournament and the Youth Conference. It is as if the Islamist Hasm, often blamed for terrorist attacks, had been on vacation as those [major] events were taking place," read one sarcastic tweet.

Others hinted that the government was eyeing the NCI's strategic location for lucrative profit. "Wait for news of the demolition of the National Cancer Institute building and statements from the government on behalf of the president that it is planning to build a world-class oncology center in the heart of the desert … but where will the funds come from for this project? From investments in the strategic land area where the old NCI once stood overlooking the Nile River," was another acidulous comment from an Egyptian Twitter user known as Noraldin El Kady.

Meanwhile, government supporters called on Cairo to deal firmly with the terrorists and their families. "Arrest their [the terrorist's] family members, prosecute and punish them for the crimes of the terrorist as they are partners in crime, inciting and aiding the terrorist by giving them shelter in their homes," was one angry Facebook comment by an Egyptian woman writing under the name Amira Abdalla.

"I give Sisi a second mandate to fight terrorism and tell the traitors that terrorism only strengthens our resolve and determination to stand behind our president," wrote another Sisi supporter in a Facebook post.

Most of the activists, however, used social media platforms to denounce the attack and appeal for donations for the victims' families and to help repair the damaged NCI building. Fearing the attack might deal another blow to the country's fragile tourism industry, which has been recovering slowly but steadily in recent months, they reminded their Facebook followers that terrorism was a global phenomenon and attacks like the recent one happen almost everywhere without people knowing when or where the terrorists will strike next.

Tourism — crucial to Egypt's economy and one of the leading sources of income for the country — had in recent months all but completely recovered from the heavy blow it was dealt by the downing of a Russian airliner in the Sinai Peninsula on Oct. 31, 2015. Russia's security chief suggested that "a terror act" had caused the crash, after traces of foreign explosives were reportedly found on the debris of the aircraft. Egypt has since been on a steady rebound, however, owing largely to improved security and infrastructure. In 2018, the country's tourism sector witnessed a growth rate of 16.5%, more than four times the international average rate of 3.9%, according to the World Travel and Tourism Council — which labeled Egypt's tourism sector "the fastest growing in North Africa."

But in an abrupt announcement on July 20, British Airways said it was suspending all flights to Cairo for one week, citing "unspecified security concerns." Germany's Lufthansa followed suit by announcing the cancellation of its flights to Cairo, but it quickly reversed its decision after only a couple of hours. The suspensions sparked outrage in Egypt, with some government loyalists branding them a "conspiracy" against the country.

It remains unclear if the suspensions were linked to specific information about an imminent aviation attack gathered by British intelligence. What is certain, analysts say, is that the government's strategy to eradicate terrorism has fallen short of achieving its goals.

"What we are seeing in fact is that the policies have instead led to a surge in terror attacks," lamented Cairo University political science professor Hassan Nafaa, an outspoken critic of the Sisi government.

"The latest attack is a very serious development. The government was quick to point the finger at Hasm, the armed wing of the Muslim Brotherhood, but that group has confined its activities to the northern Sinai where it has targeted security personnel. The fear is that new jihadi groups may be emerging or that offshoots of previously known groups are being created who may, in the future, target vital installations in the Nile Delta and Greater Cairo region," he told Al-Monitor.

"The heinous attack occurred in a populous district in central Cairo. The National Cancer Institute was certainly not the intended target of the attack. The target may very well have been the Cabinet headquarters or the parliament building, which are not far from where the explosion happened. If the government has concrete evidence that it was Hasm that carried out the attack, that evidence must be shared with the public. If not, it would be wise for the authorities to rethink their policies, which are clearly fueling radicalization."