Riyadh Governor Prince Khaled bin Bandar is monitoring the investigation into Thursday’s deadly suspected gas leak explosion in Granada district that killed a Saudi and injured 18 expatriates, a source said on Friday.

Prince Turki bin Abdullah, the city’s deputy governor, visited the site to take stock of the situation. The police and Civil Defense have launched investigations into the massive blast and subsequent fire at the restaurant on Khaled bin Waleed Street.

Maj. Gen. Suleiman bin Abdullah Al-Amro, director general of the Civil Defense, also visited the site to check on the progress of the investigation, sources said.

Meanwhile, sources said some people have left various hospitals after being treated for minor injuries. Eleven of the injured people were taken to Abanamy Hospital, two each to King Saud Medical City, King Khaled University Hospital and the Security Forces Hospital, and one to Kingdom Hospital.

According to sources, two people sustained multiple injuries in the explosion and are undergoing treatment. They refused to comment on the nationality of the injured.

Two women in a car parked outside the restaurant were also reportedly among the injured.

Earlier, Maj. Mohammad Al-Hammadi, media spokesperson of the Civil Defense in Riyadh, said those injured were of various nationalities and mostly customers.

He said the Civil Defense teams had rushed to the scene after receiving a report on Thursday. Firefighters had doused the fire, which helped to minimize the damage, he said.

Sources said a gas leak is suspected to be the reason for the explosion.

The explosion was so powerful it blew out windows of neighboring shops and cars nearby. There were also cracks in the walls of nearby buildings.