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An initial probe into a hot air balloon crash that killed 19 tourists in Egypt has ruled out any criminal activity as a cause of the accident, media said on Wednesday.

"Investigations so far by the general prosecution show no suspicion of criminal activity," the official MENA news agency reported, citing the preliminary findings of the investigation.

Ezat Saad, governor of the ancient temple city of Luxor (left), and Japanese Okumura Hatsuko (right), director of the Japanese division of an Egyptian travel agency, lay flowers in the site of a hot air balloon accident on Thursday. Khaled Desouki / Agence France-Presse

Four investigating teams were formed after Prime Minister Hisham Qandil ordered a probe into Tuesday's balloon crash in the ancient temple city of Luxor.

Luxor Governor Saad Ezzat and a delegation of Egyptian officials, as well as tourism industry professionals, visited the scene of the crash where they placed three bouquets of white flowers before observing a minute's silence.

Investigators have inspected the area in the dense sugar cane fields of Luxor, spoke to witnesses and residents and reviewed the operating company's paperwork and licenses.

According to the investigating teams, the company that operates the balloon rides, Sky Cruise, had passed a routine inspection by the Civil Aviation Ministry from Feb 13 to 15.

"The minister of aviation checked the documents of the company operating the balloon. He found everything is OK. The technical requirements were OK," Ezzat told reporters at the crash site.

Civil Aviation Minister Wael al-Maadawi said, meanwhile, that he had agreed to a request by British authorities to attend the probe.

"Things are very fresh at the moment. As the governor said, the investigations are ongoing, but if there is anything we could do, we will be happy to do so," British Consul John Hamilton said from Luxor.

"Our main concern at this time is with the people who suffered such a horrific accident, and I extend our deepest condolences to their families," he said.

The balloon, carrying 21 tourists from Hong Kong, Japan, France, Britain and Hungary, along with the pilot, was flying at 300 meters when it caught fire, exploded and plunged to earth, a security official said.

The pilot and one tourist survived by jumping out of the basket at some point before it hit the ground, said an employee of Sky Cruise, which operates the balloon rides. Both were taken to a hospital.