Unsolved crimes: A look back at recent and historic cases yet to be cracked

- Hit-and-run in Blackbird Leys

In September last year, Tarak Alam, 19, was left bleeding on the road after a car went through a red light in Blackbird Leys Road and knocked him down.

His brother Fakrul Alam, 22, said the police told the family they could no longer investigate the hit and run due to a lack of evidence.

He added: "Nothing has happened since. They don't know who had done it. We were told there was not enough evidence to carry on the investigation.

"We would like to get justice, but we never really thought something would come out.

"He [Tarak] is still in the process of recovery. He has learning difficulties and it has affected him quite a lot. It's set him back.

"There's nothing we can really do, they are the police after all."

- Major crimes still unsolved by the force include two of the city's biggest heists.

Last New Year's Eve, Goldsmiths jewellers in the Clarendon Centre was burgled, with thousands of pounds in watches being stolen. 

No arrests have been made and police appeals for the 11 masked men - shown on CCTV smashing their way into the jewellers - have proved fruitless.

Thames Valley Police announced in August it had handed over the investigation to West Midlands police force after months of 'pursuing lines of enquiry'.

Meanwhile, on Millennium Eve, the the Ashmolean Museum’s only Cézanne was stolen in a daring rooftop raid.

The £3m oil painting Auvers-sur-Oise, by the French impressionist, was stolen from the Beaumont Street museum.

It was never recovered and detectives made no arrests despite a worldwide police inquiry.

Police discovered burglars had got in through the glass roof.

- Burglary to local business 

John Goodey, whose family run Thamesdown Garden Centre in Garsington, was targeted by a thief who stole hundreds of pounds worth of garden plants.

The 62-year-old said about £600 worth of goods were stolen in August in what he thought was a planned theft after viewing the store's CCTV.

But despite supplying camera footage to the police, he was told two weeks ago the force would be closing the case.

He said: "A police officer rang me a fortnight ago to say he would have to close the case unless anything else came up.

"I was really annoyed about how him [the burglar] come back a second time. He is pictures in the CCTV.

"The police said unless they got a record of it, they would have nothing to compare it to.

"There is nothing I can do really. We have made it more secure.

"We are not a big, multi-million pound business. The annoying thing was that it was just plants."

- Historic unsolved crimes:

- Oxford University research scientist Michael Meenaghan was shot dead through the window of his Blackbird Leys home in 1994. Police never established an obvious motive for the killing.​

In 2014, a £20,000 reward is being offered for information about the murder of him

Dr Meenaghan was a lecturer at Oxford University’s Sir William Dunn School of Pathology.

Dr Meenaghan was shot at 4.30pm at his home in Monks Close, and despite dialling 999 he died of massive chest injuries before the police reached him.

- Boars Hill couple Warren and Elizabeth Wheeler, 83 and 79, were found battered to death in the living room of their cottage in October 1973. Both had been beaten with a weapon but it was never found.​

- Finnish hitch-hiker Eila Karjalainen’s decomposing body was found dumped in a wood on the Blenheim estate in November 1983. The 23-year-old had been strangled and her body lay undiscovered in Kings Wood, Woodstock, for three months.

- Taxi driver Leonard Gomm was stabbed to death in a country lane in Bletchingdon four hours after he set out to pick up a customer in June 1990. A lorry driver found the 75-year-old dad-of-three on a grass verge with a stab wound to his heart.

- Mother-of-four Nasreen Akhtar was strangled at her home in Cobden Crescent, Oxford, on March 30, 1995. A £10,000 reward was put up six years after her death but the 29-year-old’s murder remains unsolved.

- Janet Brown, an Oxford University research nurse and mother-of-three was found lying naked, handcuffed and gagged at the bottom of stairs on the morning of Tuesday, April 11, 1995. Police said the 51-year-old had been bludgeoned to death on her head by someone using a heavy object like an iron bar.

But despite statements from more than 2,000 people and a Crimewatch appeal which prompted 80 calls to Thames Valley Police, the case was never solved.

The force has offered a £20,000 reward for information which leads to an arrest.

In April 2015, a fresh appeal was made to find her murderer when the force announced new DNA technology had allowed them to build a profile of someone who was there the night she was killed.