An Israeli man has been charged with arson after he threw Molotov cocktails at the homes of African migrants in south Tel Aviv, highlighting a sharp rise in tension between locals and immigrants.

According to the indictment, which was handed down on Thursday and widely quoted in the Israeli press, Haim Mula threw seven Molotov cocktails at several apartments in the city's Shapira neighbourhood in late April.

The attack caused heavy damage but no injuries, although it has sparked a heated debate over the rising tide of African nationals arriving in the Jewish state, many of them from Sudan and Eritrea.

Some are asylum seekers fleeing persecution, while others are economic migrants. Almost all of them sneak across the border from the Egyptian Sinai and end up living in the run-down neighbourhoods around Tel Aviv's central bus station.

Official figures for 2011 showed there were some 52,487 illegal African immigrants in Israel by the end of the year, but the statistics do not differentiate between refugees and economic migrants.

In another development likely to raise tensions in south Tel Aviv, police confirmed on Friday they had arrested three Eritrean nationals in connection with the rape of a 15-year-old girl.

"Three Eritreans were arrested in connection with the apparent rape of an Israeli girl," police spokesman Micky Rosenfeld told AFP, of an incident which took place in late April but was kept under a gag order until Thursday.

Interior Minister Eli Yishai, who has come under fire for his attempts to deport migrants en masse over fears they will harm the Jewish character of the state, on Friday said Israel should release petty criminals to free up jail space for 50,000 illegal "infiltrators."

"We have a real problem," he told Israeli news website Walla!

"At the moment, there are more than 50,000 people who I cannot expel," he said.

"The security of Israeli citizens is really undermined as a result of these infiltrators and their behaviour here, so I proposed clearing out the prisons.

"The vast majority -- 99 percent of them -- are not refugees but infiltrators seeking work, and we need to expel them," he said.

Some 18 months ago, Israeli government approved the creation of a detention centre near its southern border with Egypt to house thousands of illegal immigrants from Africa seeking work in the Jewish state.

It has also begun constructing a 250-kilometres (155-mile) fence along the Egyptian border aimed at stopping the influx of migrants.

At the start of the year, Israeli Prime Minister Benjamin Netanyahu said he was planning to visit several African capitals to discuss the issue of immigration, but so far no such plans have been made public.