Palestinians gave anonymous burials on Tuesday to two men killed by Israeli forces on the Gaza border and whose unclaimed bodies stirred speculation they might have been foreign migrant workers or al Qaeda supporters.

The two were shot on 5 January while trying to clamber into Israel from the northern Gaza Strip, the army said.

Palestinian medics who collected their corpses said the men wore civilian clothes and carried no weapons. Their skin was darker than most Gazans'.

That they went unidentified was another rarity for the small Palestinian strip whose 1.5 million residents have close clan ties and whose resistance fighters are quick to celebrate their "martyrs".

Medical officials said each of the dead men had a tattoo, something that would be highly unlikely for devout Muslims.

Israel and some Palestinians say al Qaeda-style activity has a presence in Gaza, helped by foreign volunteers who slip in through neighbouring Egypt. The Hamas Islamists who rule the territory deny this.

The Egyptian Sinai has also seen a wave of African migrants who cross the border into Israel in search of asylum or jobs.

Though Gaza, under a punishing Israeli and Egyptian blockade, would seem an unattractive destination to such migrants, last month Hamas officials said they had returned to Egypt an African who had sneaked in through a smuggling tunnel.