Frank Whiteley, chief constable in Hertfordshire, said there was ''nothing to suggest anything other than an accident."
Residents said shock waves destroyed indoor light bulbs and cracked walls and ceilings.
''It was like a sonic boom," said Danny Deacon, 25, who evacuated his wife and two young children on police orders.
''Around 6 a.m., as we were sleeping, there was a mighty explosion -- a thunderclap that woke me up," said Neil Spencer, 42, who lives less than a mile from the Buncefield Oil Depot. ''It was fireball after fireball -- truly amazing."
The blast destroyed the front door of Haris Luther's house.
''I thought the house had been hit by lightning," Luther, 57, said. ''It sounded like an earthquake."
Most of the 43 people injured were treated at nearby hospitals and released after suffering cuts and bruises from shattering windows in Hertfordshire County, about 25 miles north of London. But at least two men were hospitalized, including a plant worker in serious condition, said Howard Bortkett-Jones, medical director of the two local hospitals.
Noxious fumes from the fire also affected some police officers who sealed off the area and evacuated almost 300 people to a bowling alley being used as a temporary shelter. About 25 policemen reported problems such as chest tightness and shortness of breath, Bortkett-Jones said.
There were several blasts at Buncefield terminal, which stores 4 million gallons of gasoline, diesel, kerosene, and aviation fuel, and officials warned that more could occur since it will take days to extinguish the inferno.
Panic-buying of gasoline caused long lines at some local stations, but gas companies said shortages were unlikely because there were no other problems with the country's refineries or with the manufacturing or distribution of petroleum products.
The Environment Agency said any leaking kerosene, oil, or gasoline could damage nearby rivers or streams.
