Authorities in Greece have reopened a disused Olympic venue to house migrants and refugees camped out in central Athens.

Police escorted buses carrying about 500 people, mostly from Syria and Afghanistan, from Victoria Square in central Athens to the Galatsi Olympic Hall.

It was used for table tennis and rhythmic gymnastics during the 2004 Athens Games, and is the second major Olympic venue to be reopened to accommodate refugees in recent weeks.

Yiannis Mouzalas, a migration affairs minister, promised to try to swiftly improve management of the crisis to avoid "local residents becoming susceptible to extremist, racist, xenophobic views".

Local residents and an anti-racism group held small protests at the square on Thursday, urging the government to do more to ease the effects of the crisis.