Two people were killed and two others were injured after a fire broke out at a migrant camp on the Greek island of Lesvos late on Thursday, a police official told Reuters.

The official said that a 66-year old woman and a 6-year old child were killed when a tent caught fire in the camp of Moria. Two other people were seriously injured.

Police and the fire brigade were investigating the scene, a government official said adding that according to initial evidence the fire was probably caused by accident.

Clashes broke out following the incident between dozens of migrants and police, both officials said. The government official said they were brief.

More than 6,000 migrants and refugees are stranded on the island of Lesvos, twice the capacity of state facilities.

Tensions have boiled over at overcrowded camps in the country, which is also struggling to emerge from a debt crisis, as the slow processing of asylum requests adds to frustration over living conditions.

Under a European Union deal with Turkey, migrants and refugees arriving after March 20 are to be held in centers set up on five Aegean islands, including Lesvos, and sent back if their asylum applications are not accepted.