BBC.com: European migrant crisis: Dozens die in boat off Libya

More than 40 migrants have died in an overcrowded boat in the Mediterranean, the Italian navy has said.

Many others were saved as the boat was intercepted off Libya. The navy said the rescue was continuing.

The deaths were caused by suffocation as the migrants were held in a confined space below deck, according to reports.

European officials say the plight of migrants, 250,000 of whom have crossed by boat to the continent this year, is "beyond urgent".

The Italian navy said it had co-ordinated the rescue of 1,700 people on Tuesday alone.