For the past few Saturdays, Israel Defense Forces soldiers have been preventing Arab citizens of Israel from entering the West Bank using Road 557, which stretches east from Taibeh and passes through the Avnei Hefetz and Einav settlements. Jewish citizens - few in number on Saturdays - have been allowed through.

A security source told Haaretz that passage to Jewish citizens was also barred.

The "screening" is conducted by means of a mobile military checkpoint that is set up along the Green Line at random times. On Saturday, for example, it was in place from the morning (between 9 and 10) through to the evening. Eye-witnesses said Jewish citizens were allowed through the checkpoint on Saturday.

The entry ban on Arab citizens of Israel is part of a series of changes that have been implemented recently by the IDF at the checkpoints in the Tul Karm region and are undermining the freedom of movement of Arab Israelis and Palestinian residents of the area.

In recent weeks, for example, the checkpoint has prevented employees of Palestinian laborers from transporting them to the fixed checkpoint, and the laborers have been forced to walk the three or so kilometers.

The Jabara checkpoint lies to the east of the mobile one, some three kilometers from the Green Line, with the area between the mobile checkpoint and the fixed one known as the seam area - a definition ascribed by the IDF to Palestinian areas in which the separation fence has been built east of the Green Line.

The village of Jabara, which borders of Taibeh, has been part of the seam area since October 2003, with the fence and a system of gates and checkpoints cutting it off from neighboring communities and Tul Karm.

Residents of the seam area gain access to and leave their villages by means of special permits that they show to the soldiers at the Jabara checkpoint.

For more than a year now, the defense establishment has been saying it plans to move the separation fence, which has already been built, to the west, and closer to the Green Line; and diplomats and jurists have criticized Israel's regulations with regard to the seam area. Security sources say budgetary constraints have held up plans to move the fence.

Meanwhile, passage through the Jabara checkpoint has been getting harder and harder over the past three weeks. A new gate has been installed at the northern entrance to the village, and further restrictions have been imposed on visits by relatives. Jabara residents say they feel more isolated than ever now.