Authorities said on Monday that a defective gas line or gas cylinders may have been to blame for a huge explosion that destroyed an ancient three-story structure in a bustling neighbourhood of Dhaka, Bangladesh’s capital, killing at least seven people and injuring nearly 400 others.

The catastrophic explosion in the Moghbazar neighbourhood at around 7.30 p.m. on Sunday was ruled out by police as a result of “gas accumulation,” according to the initial inquiry.

Authorities believe the structure that fell was the epicentre of the explosion since it housed a restaurant, and the bomb could have been caused by a defective gas line or gas cylinders used by the restaurant.

The bomb was so strong that it shattered the windows of nearly a dozen nearby buildings.

According to Dhaka Metropolitan Police Commissioner Shafiqul Islam, the blast severely destroyed seven surrounding buildings and two passenger buses, killing seven people and injuring 400 others, 50 of whom were gravely injured.

The seriously injured were taken to Dhaka Medical College Hospital and the Sheikh Hasina National Institute of Burn and Plastic Surgery in Dhaka.

AZM Rahmatullah Shabuj, outdoor in charge of the Dhaka Community Facility, said the hospital treated around 300 casualties, the majority of whom had cuts on their bodies or heads.

The glass fragments cut the majority of them. According to Sabuj, many people had head wounds.

In response to the notion that the explosion was planned, the Police Commissioner told bdnews, “It doesn’t appear that way to me.” People would have been devastated by splinters if that was the case, or if a bomb had exploded.”

“I learned from the firefighters that gas had accumulated here,” he explained.

Primary evidence revealed that the explosion was caused by a leak after the accumulation of gas, according to Fire Brigade chief Brigadier General Sajjad Hossain.

A restaurant on the ground floor had gas cylinders, while a shop on the second floor had air conditioning. At the scene, there were also gas cylinders… According to Hossain, an investigation has begun.

According to residents in the area, the explosion shook the city, causing panic, and television images from the scene in the country’s capital showed damaged pillars, concrete, and glass shards strewn over the street.

When the explosion happened, I was on a bus. I leapt from the bus through a small window, believing the gas cylinder had exploded… Tajul Islam, 50, who sustained injuries to his waist and complained of hearing loss as a result of the explosion, told PTI that he had never witnessed such a large explosion before.

Another witness stated that he saw a fireball pass over his head, and that the explosion turned everything dark and smoky in his proximity, with glass shards falling from the sky.

He told a television station that the boom was “that big… it terrified everyone.”

Witnesses say buses and cars collided shortly after the explosion, as panicked passengers struggled to exit the vehicles.

Following the explosion, a number of occupants from a nearby apartment block came downstairs.

“We are at a distance here,” said one of them, Mufakar Ul Islam. Even so, our apartment’s glassware was damaged in a few places.”