For the first time, a map highlighting the areas of the city where most incidents have been reported to police indicates the problem is the greatest in the city's most densely populated areas including Ribbleton, St Matthew's and Ingol.

And police have studied the figures so closely they are even able to pinpoint the hour of the week when people in Preston are most likely to fall victim to domestic violence as well as the highest risk households.

It comes as the city's police force deals with Preston's biggest ever number of reported incidents which are almost a third up on last year – from 2,225 to 2,918.

A map produced from an audit of 745 incidents from April to July 2007 shows domestic violence affected 13 in every 1,000 residents in Ribbleton council ward, with 96 incidents reported, closely followed by St Matthew's where 83 calls were made.

Brookfield had 64 incidents - equivalent to eight of every 1,000 residents there and Ingol too had a significant 59 calls.

The audit, carried out by the city's public protection unit, has highlighted midnight on Sunday as the time most people in the city risk being subjected to domestic violence.

Analysis of the 745 reports shows 38% of incidents were reported on Saturday or Sunday evenings.

A Brookfield mum-of-two, who moved out of the area to escape domestic violence, said she was not surprised the area had been highlighted.

The 42-year-old, who has been abused by several partners, said: "I think the times of the day and week highlighted are accurate.

"My partner would always wait until the kids were in bed or at school before he hit me because he knew I would not scream in case I woke them."

Det Insp Steve Hobson, of Preston Police, said: "A lot of the picture we see is down to the denser population in those areas and partly down to the socio-economic makeup.

"But the point to make is that this is just a snapshot – research shows domestic violence traverses all social groups and could be under-reported in other areas of Preston."

Officers are now hoping to throw a lifeline to potential victims in those areas via their mobile phones.

Preston Police are using a new portable Bluetooth box capable of sending messages to mobile phones within a 100m radius.

If they accept, they get an animated message containing helpline numbers. The messages cost nothing.

Click here to view a map of domestic incidents by ward