Cyclists have been warned they will continue to be fined if they persist in riding through Oxford's city centre pedestrian zones.

A second crackdown in three weeks on cyclists in Cornmarket Street and Queen Street, held yesterday, netted 71 people flouting the ban.

A similar police operation last month caught out 85 cyclists.

Between 10.30am and 1.30pm yesterday, police handed out 25 fixed penalty £30 fines in Cornmarket Street and 46 in Queen Street.

Officers have pledged to keep up their campaign to stop cyclists riding in pedestrian zones.

Pc Steve Higa said: "We will continue to concentrate on Queen Street, because there were so many doing it, we couldn't actually catch all of them.

"But I'm really pleased with how it went and this will be an ongoing operation.

"I believe we're really making an impact on Cornmarket Street but we want to concentrate on Queen Street.

"This will now be a routine operation."

As well as issuing spot fines yesterday, officers also etched postcodes on to 22 bikes, which allow stolen cycles to be returned to their owners if they are retrieved.

And two dozen cyclists picked up free high-visibility jackets, which were donated by Oxford-based logistics firm Unipart.

One suspected stolen bike was also confiscated by officers.

Student Tomasz Ras, 23, was fined £30 in Queen Street. He said: "This is a normal street with cars and buses, it's not only for pedestrians, so bikes should be allowed down here.

"It's much more dangerous when you have cars, buses and pedestrians, not bikes. I was fined for parking on double yellow lines the other day and paid just a £20 fine - now I've got to pay £30 for cycling through the city. It doesn't seem fair."

Jing Xing, 25, of Oxford, was also fined. She said: "I don't think it's fair and I don't think the sign is very obvious. I never knew and no-one has ever told me I can't cycle down here. I think next time I come I will definitely walk."

Pedestrian Valerie Ahern, from Oxford, was walking through Queen Street with her three-and-a-half-year-old daughter.

She said: "Pretty often as a pedestrian you're looking out for buses and cars. Especially here, where bikes are not meant to used.

"So, if you don't think to look out for bikes, it's an accident waiting to happen."

In the first police crackdown, on September 12, officers stopped and fined 85 cyclists in the two streets in three hours.

A week later, the Oxford Mail counted 223 cyclists in the two streets. In a three-hour period we logged 58 in Cornmarket and 165 in Queen Street.