Belongings of victims are seen amid rubble in front of the damaged facade of the National Cancer Institute in Cairo. Picture: Amr Abdallah Dalsh/Reuters

Cairo - Twenty people have been killed and 47 others injured in an explosion near a medical centre in the Egyptian capital Cairo, the Health Ministry said on Monday.

The explosion outside the National Cancer Institute took place late Sunday after a collision involving multiple cars in the southern district of al-Manyal, the ministry said in a statement.

The blast also caused a major blaze that was extinguished, state media reported.

Ministry spokesman Khaled Megahed said 47 people were injured, after earlier statements put the number at 30. He said most of them are in a stable condition, except three who remain in intensive care.

Megahed was quoted by al-Ahram newspaper as saying that at least four bodies remain unidentified.

An Egyptian man carries his son who has cancer as he walks past a police car in front of the damaged facade of the National Cancer Institute in Cairo. Picture: Amr Abdallah Dalsh/Reuters

Patients were evacuated from the oncology centre to other hospitals in Cairo shortly after the accident, but the centre had resumed receiving patients by Monday afternoon, state television reported.

The explosion rocked the broader area near the Nile River and shattered glass windows at the medical centre, witnesses said. The centre is frequented by people from across Egypt who are seeking treatment.

An Egyptian man carries his daughter who has cancer as he walks in front of the damaged facade of the National Cancer Institute in Cairo. Picture: Amr Abdallah Dalsh/Reuters

Online footage showed several cars engulfed in flames as a result of the blast. 

Cairo University, with which the centre is affiliated, denied claims that the explosion had taken place inside the site or that the blaze had spread to the centre.

An Egyptian woman cries as she walks past a police car in front of the damaged facade of the National Cancer Institute in Cairo. Picture: Amr Abdallah Dalsh/Reuters

"All the patients and workers at the centre are well," the state-run university said.

The country's top prosecutor ordered an investigation into the cause of the incident.

dpa