Italy's coastguard has said it is coordinating the rescue of up to 3,000 refugees from waters off Libya after receiving SOS calls from 18 different crowded vessels.

At least seven boats - six Italian and one from Norway - are involved in the operation to get the refugees safely off 14 rubber dinghies and four other vessels.

Sea conditions are "optimal" and there are no reports yet of capsizing incidents or any other problems, according to the Italian coastguard.

"This is not the first time we have seen this many boats carrying refugees rescued at the same time," Al jazeera's Claudio Lavanga, reporting from the southern Italian town of Scilla, said.

"This is clearly a tactic by smugglers, who wait for good weather conditions before sending out as many boats as they can."

More than 104,000 refugees from Africa, the Middle East and South Asia have landed at Italy's southern ports so far this year after being rescued in the Mediterranean.

A further 135,000-plus have landed in Greece and more than 2,300 people have died at sea while trying to make it to Europe with the help of people smugglers.

Palermo arrests

Meanwhile, police in Palermo, on the Italian island of Sicily, announced on Saturday that they had arrested six Egyptian nationals on suspicion of people smuggling following the rescue of a stricken boat on August 19.

Testimony from the 432 refugees on board suggest the vessel had been packed with more than ten times the number of people it was designed for, with many of the passengers, including a number of women and children, locked below decks.

They had each paid the traffickers 2,000 euros ($2,250) for the passage from Egypt to Italy, according to statements given to police.

On board, the crew were reported to be demanding further payment to allow those locked in the hold to come up temporarily for air.

Humanitarian organisations say the surge in the numbers of people trying to reach European Union countries is the result of conflicts or repression in East Africa and the Middle East.

They have called on European governments to shoulder more of the burden of absorbing the wave of asylum seekers and to help create safer routes for them to reach Europe.

Source: Al Jazeera and agencies