Ariel Schalit, Files, Associated Press
FILE - In this Feb. 23, 2011 file photo African migrant workers wait for free medical treatment outside the Physicians for Human Rights clinic in Jaffa, a mixed Arab Jewish neighborhood of Tel Aviv, Israel. Thousands of people from South Sudan who live in Israel must leave the country or face deportation, said the interior ministry's spokeswoman Tuesday, Jan. 31, 2012.

JERUSALEM — Now that their country has gained independence, thousands of migrants from South Sudan must leave Israel or face deportation, Israel's Interior Ministry said Tuesday.

Some 7,000 South Sudanese are believed to be in Israel, part of a larger influx of some 50,000 African economic migrants and asylum seekers who have poured into the country in recent years.

Sabine Haddad, an Interior Ministry spokeswoman, said the South Sudanese migrants will be offered voluntary deportations that include a $1,300 grant and a plane ticket home. After March 31, those caught will be deported, she said.

"Now that South Sudan has become an independent state, it is time for you to return to your homeland," a ministry statement said.

South Sudan gained independence from Sudan last July.

William Tall of the United Nation's High Commission on Refugees said Israel must individually screen asylum applications by South Sudanese to see if they are genuine refugees. Otherwise, Tall said, Israel would be in violation of agreements it signed about asylum seekers.

With the help of paid smugglers, Africans have been sneaking into Israel through its porous border with Egypt's Sinai desert since 2005.

Their numbers have surged as word spread of safety and job opportunities in the relatively prosperous Jewish state. Most have come from Sudan and Eritrea, where many fled persecution and abuse.

Israel has offered protected status to the Sudanese and Eritreans because of abuses there, allowing them to stay and work in Israel. Many have found their way to the impoverished southern neighborhoods of Tel Aviv, an area with so many migrants that Israelis have labeled it "little Africa."

The influx has sparked a national debate. Some Israelis fear the migrants will compromise the state's Jewish character and have become an economic and social burden. Others don't want their country, which grew out of the Nazi genocide of Jews in World War II, to turn away people escaping persecution.

Israel is trying to cut down on infiltration of migrants by building a a 150-mile (250-kilometer) barrier along the border with Egypt, expanding its detention facility and threatening stiff punishments to people who assist or employ them.