Domestic murders carried out by the victims' husbands or partners have been halved in London following groundbreaking research that has helped the police identify likely wife-beaters and killers.

The number of "domestic" homicides in the capital has fallen from 47 in the year up to March 2004 to 23 in the past 11 months. Scotland Yard believes the drop is largely due to a new early-warning system that uses six factors or pointers that help their officers identify would-be "domestic" killers before they commit murder.