Police fired teargas at a group of migrants on Saturday on the Greek island of Lesbos, who were protesting against a new camp being set up to replace one destroyed this week by a fire, according to local media.

Migrants had been protesting along the main road connecting the island town of Mytilene and the location of the new camp, which is due to be set up by the authorities after the Moria camp was razed earlier this week.

A journalist on the ground said the migrants were frustrated with being in refugee camps and want to leave the island, but the Greek government said on Friday they would "not be blackmailed" into relocating them.

More than 12,000 people, most from Africa and Afghanistan, have been sleeping rough since flames swept through the notoriously squalid and overcrowded Moria camp earlier this week. Some residents had COVID-19, raising fears the outbreak could spread.

Greek authorities said the fires at Moria appeared to have been deliberately lit after quarantine rules were imposed on residents who had tested positive for coronavirus at Europe's largest refugee camp.

One protester had been affected by the teargas and was shouting angrily about her treatment in the camp.

The migrants were chanting "freedom" and holding placards that read "no tent, no Lesbos, no Greece," "we need peace and freedom" and "Moria kills all lives."

"The fire made things much more difficult," said Sajida Nazari, a 23-year-old student from Afghanistan who has been on Lesbos for over a year. "We don't have food, we don't have water, we don't have freedom."

Police briefly fired rounds of teargas when some of the protesters attempted to march down a road leading to the island's main port of Mytilene, which police had blocked while work on the new tent settlement continued nearby.

The fire at the camp, which was holding four times the number of people it was supposed to, has returned the spotlight to the migration crisis facing the European Union, which has struggled to find a response that goes beyond temporary fixes.

German Vice Chancellor Olaf Scholz called on Europe to accept more refugees but the difficulty of reaching an accord was underlined by Austrian Chancellor Sebastian Kurz, who ruled out taking more in.

Greek authorities have refused any mass transfer off the island, located a few miles off the Turkish coast, despite growing hostility from local residents after years at the front line of the crisis.

But officials said they were determined to provide shelter and proper sanitation and prevent a humanitarian catastrophe.

"As of today, asylum seekers will start coming into the tents, into safe conditions," Migration Minister Notis Mitarachi told reporters at the site.

The need to bring the situation under control has been made more urgent by the fact that authorities have lost track of 35 camp residents who had tested positive for coronavirus.

Health authorities have promised to conduct rapid tests at the entrance of the new camp, with a quarantine unit ready for anyone testing positive.

(With input from agencies)