A fire destroyed at least 18 huge tents and canopies at the Kumbh Mela on Sunday afternoon, setting off explosions in multiple cooking gas cylinders but causing no human casualties, officials said.

Chief minister Adityanath was in the Mela area, about 5km from the spot in Sector-19 where the fire broke out. Authorities appealed to people to ignore any rumours and emphasised that the “Mela is going on smoothly”.

The camps destroyed include those of the Geeta Press, a key publisher of religious books; the Akhil Bharatiya Dharm Sangh Shri Karpatri Dham, an influential monastery in Varanasi; Prayagwal, a sect of local pandas (temple servitors); and the Jai Bajrangbali Sevashram, an Allahabad-based religious group.

“From my camp, I saw the leaping flames and later, black smoke. The entire sky turned dark. Although it had been a sunny day, it felt like evening had descended early,” a man who was about 1km from the site told The Telegraph.

The eyewitness said: “It was a scary sight. We started collecting our belongings so that we could run for safety if the fire reached us.”

Allahabad district magistrate Ravindra Kumar said: “The fire started from the Geeta Press camp and soon spread to the Prayagwal camp. We have controlled it and are assessing the losses.”

He said only an inquiry could establish “the exact reason” for the fire.

Vaibhav Krishna, deputy inspector-general of police in charge of the Mela area, said no lives were lost.

“We reached the spot within five minutes of the fire breaking out and controlled it by 4.20pm with the help of the fire brigade, police and other agencies. We appeal to people not to heed rumours; the Mela is going on smoothly.”

Pilgrims said the blaze took an hour to control, implying it started around 3.15pm.

Adityanath, who had done an aerial survey of the arrangements around noon before inspecting the Mela on the ground, visited the site of the fire around 5pm.

A member of the Prayagwal camp appeared to be complaining agitatedly to the chief minister about something. Security personnel quickly took him away.

Government sources said Prime Minister Narendra Modi had spoken to Adityanath to gauge the magnitude of the incident.

Sources said about 100 people were in the GeetaPress camp, where food was being distributed to devotees, when the fire broke out. About 200 people were in the Shri Karpatri camp and 50 in the Prayagwal camp.

“The Geeta Press camp is located just after the camps of the Akharas but the fire didn’t travel that side because the wind was blowing in the opposite direction,” an eyewitness said.

“At least 18 camps were completely destroyed. We first heard a blast, which was followed by several blasts after 10 minutes. We later came to know that these were exploding LPG cylinders.”

As the fire brigade tried to douse the fire, eyewitnesses said people from the affected camps ran out carrying their belongings.

“Four tents had caught fire when the police arrived and started fighting the blaze. But a dozen more camps caught fire. Over a dozen fire tenders arrived thereafter and controlled the blaze,” a pilgrim said.

“The flames were very high. They could have spread to most of the Mela if more cylinders had exploded.”