Israeli soldiers are refusing to allow entry to a group of about 20 Eritrean refugees trapped for six days between Egyptian land and a high steel fence that Israel has erected along its southern border. Despite high temperatures and lack of shade, the soldiers have been instructed to provide only limited quantities of water.

The Israeli interior minister, Eli Yishai, said Israel "must act with a heavy hand". The country had "a very clear policy and a border fence", he told Army Radio. "We cannot let them enter."

The group, which includes two women and a child, are refusing to return to Egypt. Technically, they are on Israeli territory but the recently erected fence prevents them advancing.

According to Israeli media reports, one of the women was visibly pregnant, but migrants told the soldiers watching the group she had miscarried.

The refugees have not been offered food since arriving at the spot in the northern stretch of the Israel-Egypt border last Thursday. Temperatures in the desert area are expected to peak at about 33C on Wednesday.

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