Thousands demonstrate against detention of illegal migrants

Thousands of people have demonstrated in cities across Australia to demand the release of illegal immigrants imprisoned in remote detention camps.

Some 3,000 people took part in the biggest protest in Melbourne, where speakers denounced the detention of migrants, saying they had done nothing wrong.

Protests were also held in Sydney, Brisbane and Perth.

"We want to send a message to the Australian government that the treatment of refugees is just not good enough," Free the Refugees campaign spokesman Trish Corcoran told the Sydney protest.

"We have the harshest refugee laws in the western world and it is totally unnecessary to lock people up in the desert when their only crime is to flee from a country where they are suffering persecution," she said.

Police watched the protests, which were peaceful.

Hundreds of illegal migrants are arrested every year for trying to sneak into Australia in search of a better life, many of them from the Middle East and the Indian subcontinent. Most brave long and dangerous voyages on decrepit boats run by Asian smuggling gangs.

Detained migrants are held in camps, some of them in the desert, while their appeals for asylum are heard. Detainees are expelled if their asylum appeals are rejected.

The camps have been hit by a wave of riots in recent months, with detainees claiming conditions are harsh and inmates are mistreated by guards.

The government says conditions in the camps are adequate and the violence stems from some refugees trying to avoid being deported.