Rival bands of traffickers are fighting over the lucrative migrant business in Libya and even intercept boats to extort the passengers, the head of an EU operation against smugglers said Thursday.

"There is a certain rivalry" between different networks with people trying to cross the Mediterranean by boat caught in the middle, Enrico Credendino, head of the "Sophia" military operation told a parliamentary commission.

The bodies of 85 migrants have been found washed up on the coast of Libya, a major departure point for the sea crossing to Europe, the Red Crescent said Monday.

Since Tuesday, volunteers have recovered dozens of bodies of migrants in an advanced stage of decomposition on beaches near the capital, spokesman Mohamed al-Misrati said.

Authorities in Libya's militia-held capital have called for a freeze in U.N.-mediated peace talks until the military of the internationally recognized government halts an offensive in the east.

Khalifa Ghweil, prime minister in a Tripoli-based parallel administration, "strongly" condemned the talks being held in Morocco between Libya's rival parliaments.

U.N. envoy Bernardino Leon told Libya's warring parties Tuesday there would be no more negotiations on a U.N. peace plan and it was time for them to take it or leave it.

As talks in the Moroccan seaside resort of Skhirat broke up for the Muslim Eid al-Adha holiday that runs from Wednesday until Sunday, Leon told delegates from Libya's rival parliaments that when they returned he expected a straight yes or no answer.

The Libyan coastguard said it rescued 215 migrants Sunday from two boats in the Mediterranean, including more than 50 women, a day after Italy said over 4,500 people were saved off Libya.

The Tripoli-based government, quoting a coastguard spokesman, said the migrants were of different nationalities.

The United Nations accused the army of Libya's internationally recognized government on Sunday of deliberately trying to sabotage crunch peace talks with a new offensive in second city Benghazi.

The U.N. Support Mission in Libya called for an immediate halt to the offensive announced by controversial army chief Khalifa Haftar on Saturday to give peace talks between the country's rival parliaments a chance.

Twenty rescue operations Saturday picked up over 4,500 people off the Libyan coast, according to the Italian coastguard, which was coordinating the response for yet another boat in distress in the Mediterranean.

Among those taking part was Doctors Without Borders ship Bourbon Argos, which told AFP it had rescued over 800 people, who were expected to be brought to safety in Italy along with the rest of those saved.

At least seven bodies were recovered, including a child, and four pregnant women were listed as missing, as an oil tanker rescued 102 migrants from the Mediterranean off Tripoli on Friday.

"We were some 22 nautical miles northeast of Tripoli when at around 9 am (0700 GMT) we spotted ... a group of people in the water," said Mohammed al-Kone, an officer on board a Libyan oil tanker.

Lawmakers from Libya's internationally recognized parliament agreed Friday to return to peace talks after resolving an internal dispute, reviving hopes that a deal is within reach, a U.N. envoy said.

Spanish diplomat Bernardino Leon's plan calls for an accord on the formation of a national unity government to be reached by Sunday, in time for the U.N. General Assembly in New York which continues through October 6.

Libya's coast guard said Thursday it had intercepted a Russian-flagged tanker suspected of carrying an illegal shipment of petrol and detained 12 crew members from Russia.

"We received a signal on the presence of a ship transporting an illegal cargo of petrol near Zuwara," 160 kilometers (100 miles) west of Tripoli, on Wednesday, Captain Taoufik Mohamad Assakir, operations chief for central Libya, told AFP.