Italian navy and coastguard vessels have rescued more than 1,000 migrants off the tiny island of Lampedusa in the past 24 hours, Italian officials say.

On Thursday 823 migrants were picked up from four overcrowded, rickety boats. The migrants were mainly from Egypt, Tunisia, Iraq and Pakistan.

On Wednesday 233 migrants were saved in a separate operation. They were from Pakistan and several African countries.

Lampedusa has struggled to cope with thousands of migrants coming ashore.

The latest boatloads of migrants have been taken to Sicily.

Last October more than 400 people drowned in two shipwrecks near Lampedusa, which is the closest Italian territory to North Africa.

Many of the victims were from Eritrea and Somalia. But in the past year the migrant numbers from Syria have soared because of the civil war there.

Meanwhile Greek coast guards rescued 85 migrants off the island of Astypalaia on Thursday.

Greece and Italy are the main Mediterranean entry points for migrants fleeing poverty and violence in Africa and Asia.

The BBC's Alan Johnston in Rome says the Italian authorities used to expect the flow of migrants to diminish in winter, when crossings are riskier in the much colder, stormier conditions.

But the fact that so many have been rescued in the last few days - in the depths of winter - is evidence of the desperation of those attempting to reach Europe, and begin new lives, he says.

Extra surveillance

Italian officials say Thursday's operation off Lampedusa involved six military vessels and several helicopters. The 823 included 30 women and 42 children.

The migrants rescued in Italian waters on Wednesday were reportedly from Eritrea, Nigeria, Somalia, Zambia, Mali and Pakistan.

In the past, human rights organisations, including the UN refugee agency UNHCR, have strongly criticised Italy and Greece countries for "push-backs" - a policy of sending migrants back to their point of departure.

After last year's Lampedusa disaster the Italian government launched an operation called "Mare Nostrum", mobilising extra warships and aircraft to prevent further tragedies.

The country has also called for help from other EU states to deal with the migrant influx.

The European Commission has asked for more resources for joint sea patrols, and more co-ordination with countries that migrants embark from, such as Libya.