Last year, 20-year-old Banaz Mahmod was garroted with a shoelace in her London home before her body was stuffed in a suitcase and buried in the back garden of a house more than 120 miles (190 km) away.

The killing was ordered and carried out by her father and uncle and their associates. Her crime was to have fallen in love with another man after her arranged marriage fell apart because her husband had been violent.

Mahmod's murder was a so-called "honor killing", carried out by families or communities who believe girls have brought disgrace, for example by refusing a forced marriage.

The United Nations estimate there are 5,000 honor killings worldwide every year but the issue was almost unheard of in Britain until a 2004 Crown Prosecution Service (CPS) conference.

Nazir Afzal, the CPS director who organized that conference, said the situation in Britain was worse than they had thought and a growth in religious fundamentalism had helped make it worse.

"Even I had no idea quite frankly how serious a problem it was, how many communities were affected, how many people were affected," Afzal told Reuters.

"Murder is just the tip of the iceberg. You have a substantial number of kidnappings, false imprisonments, serious assaults, which are also carried out in the name of honor."

The CPS prosecutes about a dozen "honor" murders a year but Afzal believes the true number of killings is much higher.

"We have cases of murders that take place abroad -- people who are taken and killed abroad -- so they obviously don't come into our figures," he said.

"We also have a substantial number of missing persons."

In the wake of the 2004 conference, police launched a review of about 120 cases where women had disappeared or appeared to have committed suicide. Afzal said about 20 were now suspected of being honor-related crimes...