A £5,000 reward has been offered in a bid to track down a robber who wielded a gun in a raid at a travel agent.

Police have revealed CCTV footage in the hunt for the attacker who struck at Co-op Travel, in London Road, Headington, Oxford, in February.

It was the third raid of its kind on the shop in two months and during the first two robberies, £50,000 was stolen.

The footage shows the wanted man enter the branch with an accomplice.

The attacker's handgun is clearly seen on the CCTV footage as he ushers three terrified female staff into a back room.

Det Insp Simon Morton said: "Anyone who walks into a travel agent with a firearm, I would suggest, is dangerous and must not be approached. There is no doubt that if someone knew this man, they could pick him out from these pictures.

"It is a horrible and harrowing thing to happen once and that shop has been put through it three times now."

Both men left empty handed believing they had set off the alarm. They ran away in the direction of Windmill Road.

One man has been arrested and charged in connection with the incident.

During similar robberies in December and in February, a gang of robbers escaped with a total of £50,000 in sterling, foreign currency and traveller's cheques.

Police are still considering whether the three raids are linked.

Mr Morton added: "It is possible they are connected, but we cannot say for sure at this stage. There are similarities in the offences, but we are not necessarily linking them.

"It is a harrowing experience and one which we would hope no-one ever has to go through.

"We are appealing to the criminal fraternity who may know this man. We are appealing to associates, family and friends. Someone knows who he is and it is important we get through to that person."

After the first of the three raids, on December 30 last year, one of the female travel consultants told the Oxford Mail the robbers claimed they were armed and demanded cash.

They held female travel consultants - including a teenage girl who emerged from the toilet in the middle of the raid - in the back office before stealing £25,000, including foreign currency, from the safe. The second raid took place on February 2.

Midcounties Cooperative has offered £5,000 for any information which leads to a successful prosecution. Co-op spokesman Adrian Barradell appealed for anyone with information to come forward.

Anyone who can help should call Oxford CID on 08458 505505 or Crimestoppers anonymously on 0800 555111.