Most of the asylum seekers who were left homeless after fires ripped through their camp on Lesbos island have moved to a new temporary site, Greece's migration ministry said on Saturday.

Forced to sleep rough for days after the blazes wrecked their Moria camp last week, roughly 9,000 of the 12,700 homeless have now settled at the hastily built site of white tents.

Some have resisted entering the new camp fearing they may get stuck there, but a police operation combined with threats to discard the asylum requests of those who refuse has helped to push thousands into the facility.

The destruction of Moria, a notoriously overcrowded and dirty camp, strengthened calls from locals and humanitarian organisations for the migrants to be moved off the island.

Six Afghans have been arrested over the blazes, the first of which happened on September 8 shortly after 35 people were found to have contracted coronavirus.

The UN refugee agency has warned Greece that the new camp can only be temporary, saying on Friday that "what may be deemed adequate in terms of shelter and services during emergency situations is not appropriate for the longer-term".

All those entering the camp are given a virus test and 214 cases have so far been detected, according to the migration ministry.

Access to all migrant camps has been restricted since March because of the pandemic — a move criticised by aid groups that point out that measures began to be lifted elsewhere in Greece in May.