Armed police are locked in a stand-off with a gunman after a dramatic shootout in Oxford city centre on Monday.

A siege is under way as officers try to negotiate with the armed man in a property in Paradise Square.

Norfolk Road is in lockdown after shots were fired from a residential property in Paradise Square before armed response officers returned fire.

One person was treated by paramedics at the scene for injuries that aren't life-threatening, but no further details were given.

Armed officers descended on the residential property at around 1.15pm after witnesses reported hearing up to five gunshots.

Members of the public have been warned to avoid the area, but police say the incident is not being treated as terrorism.

A witness said more loud bangs were heard later on Monday night, which sounded like gunfire, followed by shouting.

Speaking to the Press Association just after 10pm, she added: 'The situation is very much ongoing.'

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Armed police are locked in a stand-off with a gunman after a dramatic shootout in Oxford city centre

A siege is under way as officers try to negotiate with a man in a property in Paradise Square

A siege is under way as officers try to negotiate with the armed man in a property in Paradise Square, Oxford

A cordon has been rolled out blocking access to Paradise Square, where the stand-off is taking place and residents have been warned to stay inside.

Neighbouring Paradise Street and Castle Street have also been shut, and residents are being told they cannot return to their homes in that area.

A convoy of masked policeman were seen entering the cordon around the Oxford shooting, with at least four individuals spread between two vehicles.

David Gallagher, a spokesperson for South Central Ambulance Service, said one person was being treated in an ambulance near the scene, for injuries that are not life-threatening.

He was not able to give details about the injuries, but said: 'We have another ambulance and a rapid response vehicle at the scene.

'Further resources are en route to support those already at the scene, but there are currently no further patients.'

Norfolk Road is in lockdown after shots were fired from a residential property in Paradise Square before armed response officers returned fire

Armed officers descended on the residential property at around 1.15pm after witnesses reported hearing up to five gunshots

A cordon has been rolled out blocking access to Paradise Square, where the stand-off is taking place and residents have been warned to stay inside

There's a heavy police presence near Paradise Square where armed officers are locked in a stand-off with a gunman

A line of ambulances were parked in Castle Street. At about 5pm, paramedics were seen carrying a stretcher of medical equipment towards Paradise Square.

Fire engines, police cars and sniffer dogs were also seen at the scene - which is just a 10 minute walk from Oxford University's Pembroke College,

Police helicopters were seen overhead as well, circling the area in a bid to get information on the siege.

A nearby resident, who did not want to be named, said he first heard two loud bangs early in the morning, but thought it was just Bank Holiday fireworks.

Later that day, he said he witnessed the start of the altercation between an armed man and the police, during which he heard around 20 shots exchanged.

He said: 'I was frightened. I saw how easy he got down from his balcony, and I was terrified for a second, thinking he was going to come get me.

'He was shooting from the balcony and then he climbed down the balcony, he was in the gardens and police were kicking the back doors to other gardens trying to get him.

'Then he climbed back up and shot again. And that's when they shot him in the head I think and in the chest.

'I could hear a female negotiator and an armed response man trying to get him to put his hands up, let go of the gun, keep his hands on show and things like that.'

The resident said he heard a man repeating that he needed medical treatment, before getting 'really angry, shouting, roaring at them (the police)'.

He said the whole street had been evacuated and families were getting anxious about where they would be able to spend the night as darkness fell.

One resident in Paradise Square, who asked not to be named, said: 'I was coming home with my kids and police wouldn't let us into the street.

'I heard about five gunshots and there was an armed response.

A gunman exchanged fire with police in a dramatic shootout that led to a number of streets in Oxford being sealed off on Bank Holiday Monday

Armed response officers descended on a residential property in Paradise Square after witnesses reported hearing gunshots at around 1.15pm

'Flats have been evacuated and police were trying to talk someone down from their balcony.'

The resident added he was eventually allowed back into his house, but was told to stay inside.

A woman, who asked not to be named, said the gunfire was 'scary', but added the incident became 'almost surreal' as the siege went on.

She was sat on her balcony when she heard loud bangs, shouting and dogs barking on Monday afternoon.

'After a second round it became apparent these were gunshots so I rushed inside,' she told the Press Association.

'There was a couple more shots, three spurts in total, still a lot of shouting and barking. I heard a man shout 'show me your hands' repeatedly.

'The shouting continued and only quietened down an hour later or so, between now and then there have been bursts of shouting, barks and helicopters.

'I've heard no more shots since though. The entire area outside my flat is sealed off, and there is a police officer with a dog stationed a few metres from the balcony.'

Just a 10 minute walk from Oxford University's Pembroke College, ambulances, fire engines, police cars and dog units were seen at the scene

The armed response unit was deployed to the city centre and officers were seen combing the area with sniffer dogs after reports that a man had access to a firearm

Shots were fired at officers from the property and they returned fire, Thames Valley Police said on Twitter

One person was treated by paramedics at the scene for injuries that aren't life-threatening, but no further details were given

Dean Dwyer, 21, added that he was on his way to meet friends at the pub when he heard police officers shouting.

He said: 'They shouted, 'armed police, show me your hands' quite a few times. Then they asked us to move along the street quite hastily.

'So I went into the pub, and that's when I heard the gunshots.'

Janet Borgerson was in the nearby Hotel Malmaison when she heard 'explosive cracks' she thought were holiday festivities before another series of 'loud bangs'.

'Again, I thought the second round were firecrackers. I noticed hotel bar staff ushering people inside,' she told the Press Association.

Ms Borgerson, who is visiting the city from America, said guests were later told by an armed officer that they were 'perfectly safe' and allowed to leave the hotel.

'Because the shooting was directly behind the hotel block in which my room is I did feel worried that someone with a larger weapon could be a threat.

'But the police were quickly on site and after 45 minutes or so inside, and then briefed by police, they seemed to have the shooter isolated,' she said.

'To the police after a short time, this was definitely a 'keep calm and carry on' moment.'

One resident took to Twitter and said: 'Armed security says, 'just carry on..'

'Seems security has shooter in cordoned area & are not worried about wider threat. Security says we may hear more gunshots.'

Residents had reported hearing 'a series of loud bangs' in the area before an armed response unit was sent in.

A 27-year-old masters student at the University of Oxford, who lives in Paradise Square, said: 'I saw a bunch of cops running down the road. They had shields and massive guns.

'I went outside to see what was going in but the police told me to go in.

A number of roads were closed in the area and residents warned to stay inside their homes

Some Oxford residents have taken to social media to warn people to steer clear of the area

'I heard some shots, then there was quite a period of silence, and then some more shots.'

The woman, who did not want to be named, added: 'I heard more than five shots total definitely. It all happened at about half past 2. I don't know what happened at quarter past 1.'

'The police said 'stay away from the windows at the back of the house'.'

'I was coming home with my kids and police wouldn't let us into the street,' one resident in Paradise Square told the Oxford Mail.

'I heard about five gunshots and there was an armed response.

'Flats have been evacuated and police were trying to talk someone down from their balcony. Police told me to stay in my house.'

A spokesman for Thames Valley Police said: 'Armed response officers are at a residential property in Paradise Square following a report shortly after 1.15pm today that a man had access to a firearm.

'Shots were fired from the property and police returned fire.

'Officers are currently negotiating with the man as they work to resolve the situation.

'Norfolk Road is closed while officers are dealing with the incident and members of the public are asked to avoid the immediate area where emergency services are present.'

Superintendent Joe Kidman, Oxford Local Policing Area Commander said: 'People in Oxford will notice an increased police presence in the area while officers are dealing with the incident, which is contained and taking place at a residential property.

'If you have any concerns or wish to raise anything please approach and speak to an officer or call the non-emergency number 101.'