The lay-bys, one on the southbound carriageway of the A446 near junction four of the M6 and one on the A452 near Sidings Wood, were shut on Monday.

Warwickshire Police said they were used for sexual encounters between men and motorists stopping in the lay-bys were subjected to violent hate crimes.

Police believe many more crimes have not even been reported.

'Sex environments'

They say there is a history of violent crime near both lay-bys.

The lay-bys, police said, had been used as "public sex environments" by men and that victims had been subjected to serious assaults, robbery, blackmail and damage to their vehicles.

The crimes were carried out because the victims were gay or thought to be gay and this also led to random attacks on drivers who were simply using the lay-bys for other reasons.

The Highways Agency held a public consultation over the issue last year which resulted in this week's closure of the lay-bys.

Despite measures such as high visibility police patrols and setting up a homophobic attack hotline, police said it was decided the lay-bys should be closed in the interests of public safety to prevent further violence.

Ch Insp Chris Lewis, of West Midlands Police, said: "One of the difficulties we have had is trying to find out facts and to get information because obviously by the very nature of the activity there, things tend to be very sensitive, very secretive.

"A number of people do target the lay-bys and these individuals do have prejudices."