Families of several Palestinian prisoners threw shoes at the convoy of UN Secretary General Ban Ki-moon as they entered the Gaza Strip from Israel Thursday morning, witnesses said.

The prisoners' families, gathering near Erez crossing, also tried to attack Ban's vehicle with batons but were stopped by Hamas policemen.

The protesters said they were disappointed with the agenda of Ban's third visit to Gaza, which does not include a meeting with the families of the prisoners held by Israel.

The demonstrators held banners blaming the international organization for not condemning the arrest of some Palestinian lawmakers and the blockade against Gaza by the Jewish country.

Israel imposed the closure on Gaza after the Islamic movement Hamas took over the Palestinian enclave in 2007.

The UN chief headed to southern Gaza to inaugurate a housing site the UN Relief and Works Agency (UNRWA) had been building for years. The project was interrupted by the closure but was later resumed after some restrictions were eased in 2010.

During his few hours in Gaza, Ban is not scheduled to meet officials from Hamas, which Israel, the United States and most European countries considers to be a terrorist group.

The UN is a member of the Quartet of Middle East peacemakers, which also include the United States, the European Union and Russia.

The Quartet recently facilitated six rounds of "exploratory" talks between Israel and the Palestinians in Jordan to help restart their direct peace negotiations that broke down in 2010.