A huge explosion and fire has caused the collapse of a block of flats leaving "a number injured" in Oxford.
Thames Valley Police said in a statement the blast happened at around 4.45pm (GMT) in the area of Gibbs Crescent and Osney Lane on Tuesday 14 February. The blast, close to the marina, has resulted in the area being cordoned off.
The South Central Ambulance Service, operating in the area, said a gas main had exploded and four flats had then collapsed.
It is not known how many people were in the building and it is understood one woman is being treated for her injuries.
A spokesman for Thames Valley Police said: "A number of people have sustained injuries and are currently being treated by emergency services. Members of the public are advised to avoid the area while officers and other emergency services are on the scene."
Chief Inspector Marc Tarbit, of Oxford police, said: "We are keeping an open mind as to the cause of the incident however we are not treating it as terrorism-related. We are continuing to ask members of the public to please avoid the area to allow the emergency services to work at the scene.
Footage and photos taken from close to the scene show a fireball over the building as flames threatened to destroy boats moored nearby.
Juliette Sargeant, who lives nearby, told the Oxford Times: "It was an enormous boom, it was like a sonic boom. It sounded like a bomb had gone off. It was very very scary, I was quite shaken."
The structure is a three-storey block of four flats with five ambulances.
South Central Ambulance Service spokesman David Gallagher told The Mirror: "We don't know who was in the building at the time. We have to wait for the Fire Service to put the fire out and go through the building.
Surrounding buildings were evacuated and members of the public were advised to avoid the area as the fire raged on for hours.
The cause of the blaze has not been officially confirmed but eyewitnesses suggest it could be due to a gas leak. One eyewitness told the BBC there was one small blast, followed by a much larger explosion five minutes later.
Chief Inspector Marc Tarbit, of Oxford police, said: "Our officers are currently on the scene working closely with our colleagues from the other emergency services. We are keeping an open mind as to the cause of the incident however we are not treating it as terrorism-related.
"We are continuing to ask members of the public to please avoid the area to allow the emergency services to work at the scene.
A spokesman for Oxfordshire County Council said: "Two people have been treated for minor injuries and one was taken to the John Radcliffe Hospital in Oxford. A small number of people are unaccounted for in this ongoing investigation."