Israel's Supreme Court has ordered the release of "illegal migrants" or refugees held for more than a year at a detention centre in the Negev desert.

On Tuesday, 750 people were released in small groups with 428 scheduled to be freed on Wednesday, the prison service spokeswoman said.

But those freed were left with few options, after being barred from two cities.

Inside Story: Migrants or refugees?

Detainees leaving the facility waited at bus stops for rides and wondered where they would live after being banned from Tel Aviv and Eilat, in the face of hostility from many residents, the AFP news agency reported.

As in other parts of the world, immigration has become a high-profile issue in Israel, with right-wing politicians calling for action to limit it and activists urging the government to accept people from countries such as Eritrea.

"We don't know where to go, where we're going to sleep tonight," said Salah, a 33-year-old Sudanese man who has been in Israel for nine years, including 20 months at the detention centre.

Nissan Ben Hamo, the mayor of Arad near the Dead Sea, said on Facebook that he would call on residents to "defend their city" if it became necessary.

He ordered staff and local police to deploy to the entrance of the city to block the freed migrants from entering.

The Supreme Court two weeks ago overturned a provision of a law that would have allowed "illegal migrants" to be held for up to 20 months without trial.

It ruled that "illegal migrants" held for more than a year should be released within two weeks.

Refugee policy

Israel says more than 45,000 "illegal migrants" are in the country, almost all from Eritrea and Sudan.

Most of them have not been detained and live in poor areas of southern Tel Aviv, where there have been several protests over their presence. 

In September 2014, Human Rights Watch (HRW) said during the first part of 2014, Israeli authorities had employed an "unlawful coercion policy" to force almost 7,000 African refugees to leave Israel, putting them at risk of imprisonment and torture upon returning to their home countries.

Israel has never created a clear policy on refugee status, and does not officially process refugee claims.

It grants most asylum seekers "temporary group protection", also known as "deferred detention", which allows them to remain in the country, but doesn't provide them with a work permit, healthcare, or other social services.

The government has defended its policies by stating that it cannot absorb the refugees while also preserving the state's Jewish character.

Since its creation in 1948, Israel has recognised less than 200 asylum seekers as refugees, according to human rights groups.

Source: Agencies