The Israeli peace activist Prof. Jeff Halper, who sailed to Gaza with other demonstrators from around the world Saturday, was arrested yesterday as he crossed into Israel from the Strip through the Erez crossing.

Halper, who heads the Israeli Committee Against House Demolitions, arrived in Gaza on one of two small ships that carried activists protesting against Israel's blockade of the Gaza Strip.

Israeli authorities allowed the boats to reach the enclave "to avoid any provocation" by the leftist activists.

Halper took part in the celebrations held by the Palestinians to honor the blockade-breaching boats, but he chose not to meet with Hamas leader Ismail Haniyeh.

From the Gaza Strip, Halper was interviewed by much of the Israeli media.

The two boats are scheduled to leave Gaza for Cyprus tomorrow, but Halper, who lives in Jerusalem, tried to return home through the Erez crossing and was arrested.

Halper had told Haaretz that he expected to be questioned by the authorities but did not think they would harass him.