Police patrols are being stepped up in Blackbird Leys after the reappearance of daylight crack and heroin dealing. The increased presence was prompted by information passed to them that a gang was peddling Class A drugs from a network of alleyways on the estate.

Last night the man in charge of policing the estate admitted his officers might have inadvertently allowed dealing to reoccur by focusing on other issues on the estate.

Frightened families living close to the problem said they were too scared to leave their homes after dark because they were intimidated by addicts hanging around waiting to score.

Now, in an effort to allay their fears, police have vowed to increase patrols near alleyways linking Warburg Crescent with Cuddesdon Way and Balfour Road with Druce Way.

Neighbours welcomed the pledge, but said fear of reprisals meant they had reservations about sharing information with the police.

A mother-of-two, who asked not to be named, said she would not venture out of her flat in Warburg Crescent after dark because of the dealers.

She said: "I’m not happy. We’ve got shady characters hanging around on the steps to my flat.

“I’m scared, especially when it gets dark. The addicts are nasty, unclean characters. There are people urinating down the alleyways and there is spit on the stairs."

A father-of-two, also from Warburg Crescent, said: "I don't want it around here. When my little girl goes out to play I don't want her to see that sort of thing."

In August last year, the Oxford Mail reported that dealers were using the alleyways and a nearby row of sheds as a shooting-up parlour. Police stepped up patrols then and the sheds were demolished — two factors which neighbours said caused the dealers to disappear.

But within the past month, they said, a woman and two men, all believed to be in their 30s, had started to meet addicts in the alleyways to make quick transactions.

The mother-of-two added: "When they got rid of them last time it was brilliant. For the majority of the summer we had no problems. Now it’s even worse than it was before."

Insp Andy Storey promised he would step up patrols around the alleyways, although he could not give any guarantees about how many extra patrols would be undertaken.

He said: "The difference was quite noticeable when we stepped up patrols before.Residents were coming up to us and saying there had been a lack of activity. It may be that we’ve taken our foot off the pedal a bit.

"Now that we know the dealers are back we will revert to what we did previously.

"We can redirect the neighbourhood team's efforts to Balfour Road and Warburg Crescent. If it worked before then I’m not going to reinvent the wheel."

An Oxford City Council spokesman said its street wardens had been told about the drug dealers and were liaising with police.