Israel’s Parliament, the Knesset, on Tuesday , banned lawmakers from visiting Palestinians who are being held in Israeli prisons for security offences

The move followed a police investigation into suspicions that Israeli-Arab lawmaker Basel Ghattas smuggled mobile phones to Hamas prisoners in the Ktzi’ot prison in southern Israel.

The Knesset House Committee approved the move in a 12-1 snap vote, a day after the change was first proposed by Internal Security Minister Gilad Erdan.

The committee did allow some visits, saying the Knesset Speaker and Chairman of House Committee would publish a list of lawmakers from the coalition and opposition who would be allowed to hold such visits in order to oversight the incarceration conditions.

As of the end of 2016, there were about 6,295 Palestinian security detainees in Israeli prisons, according to figures by B’Tselem, an Israeli human rights organisation.

Most of these prisoners took part in the struggle against the Israeli occupation of the West Bank and Gaza Strip.

Ghattas is a lawmaker with Balad, a nationalist party that has frequent confrontations with the government.

After his four-hour interrogation, he said the accusation against him are baseless and part of a political prosecution.

Israel’s Arab minority makes up about a fifth of the Israeli population.

Arab citizens of Israel are Palestinians who stayed put during Israel’s 1948 Independence War.