Madrid  - The number of undocumented immigrants known to have tried to enter Spain dropped by 24 per cent to about 37,000 people in 2008, Interior Minister Alfredo Perez Rubalcaba said Monday.

The figure refers to would-be immigrants arriving by air, road or sea. The number of mostly African migrants arriving by boat went down nearly 26 per cent.

Rubalcaba attributed the decline to more efficient frontier controls and repatriations in cooperation with the migrants' countries of origin. dpa