The Egyptian Ministry of Health announced the high number of victims of the explosion, which occurred yesterday in the vicinity of the Oncology Institute in the Manial area (central Cairo); 19 people and injuring thirty others. There was no official statement indicating that the explosion was caused by an attack.

The Minister of Health, Hala Zayed, said that the injuries caused by the explosion ranged from extremely dangerous to medium, and the evacuation and transfer of 54 cases of the patients of the Institute to other centers.

"There are three to four critical cases in intensive care at Nasser Institute Hospital. The rest of the injuries varied between minor and moderate fractures, in addition to cases of burns of varying degrees and sever injuries in various parts of the body," Health Ministry spokesman Khalid Mujahid said on his Facebook page.

At least two cars were burnt at the site of the explosion in front of the Oncology Institute. The scene is messy and not yet clear what happened pic.twitter.com/AVhS9tpGFV

- Omar Elhady (@ElHady) August 4, 2019

The Interior Ministry said the blast was caused by a private car that was driving in reverse direction on Corniche El Nile Street in front of the Oncology Institute before three cars collided, causing the explosion.

Serious damage
The official Egyptian News Agency reported that the explosion caused serious damage to the front of the Oncology Institute, and the damage extended to some rooms inside the Institute.

Videos circulating on social networks showed fire engines trying to control a huge fire and a number of private cars damaged by the blast.

An explosion yesterday left serious damage to the front of the Oncology Institute in Cairo and in some of its rooms (European)

Egyptian Attorney General Nabil Ahmed Sadeq ordered an urgent investigation into the blast. A team of prosecutors, forensic experts and explosives men arrived in the blast area.

Patients and staff
The Cairo University Media Office said in a statement that all patients and workers in the Oncology Institute was fine, pointing out that the incident occurred near the administrative building away from the patients' rooms, explaining that immediately after the incident an emergency room and operations were established to follow up the developments. Al-Aini Hospital to receive any casualties of the accident.

Cairo University President Mohamed Othman Al-Khasht declared a state of emergency, called medical staff to take care of the patients of the National Institute of Oncology, and ordered Al-Khasht to form technical committees to inspect the Institute's facilities and ensure that it was not damaged as a result of the accident.

If the Oncology Institute exploded in the second round because of an oxygen cylinder called Mapicoloa, how would the fire be left outside the building and the fire in front of the building? (Video-visualized off-the-counter building for # Manial Oncology Institute) pic.twitter.com/vr0il4YIHG

- mo-stache (@abugabal) August 4, 2019

Egyptian journalist Mohamed Mounir told Al Jazeera that it was confirmed that the accident was caused by an explosion outside the Institute of Oncology, but added that the force of the explosion was not consistent with the fact that the accident was a collision of a private car with other cars.

At first, the accident was caused by a gas pipe explosion at the Oncology Institute, but the residents' testimony was that the explosion was caused by a collision of cars outside the state health institute.