Updated

A former college professor who pleaded guilty to aiding a Palestinian terrorist group has begun a hunger strike to protest "continued government harassment," his supporters said.

Sami Al-Arian stopped eating after being held in contempt for refusing to testify before a grand jury in Virginia, the Tampa Bay Coalition for Justice and Peace said in a news release Tuesday.

Al-Arian claims he is surrounded by rats and cockroaches in prison, and is forced to wear dirty and inadequate clothing.

Al-Arian, who has less than 18 months left on a 57-month sentence for aiding the Palestinian Islamic Jihad with nonviolence activities, was found guilty of contempt in November in federal court in Alexandria, Va.

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Attorneys for the former University of South Florida professor contend that the terms of his plea agreement freed him from further cooperation with the government. But a federal judge disagreed. An appeal has been filed with the 11th U.S. Circuit Court of Appeals.

When called before the grand jury in Alexandria, Va., on Oct. 19, Al-Arian refused to answer questions about the International Institute of Islamic Thought in Herndon, Va., which funded Al-Arian's Palestinian think tank in Tampa.

Al-Arian's status will be reviewed every six months, for up to 18 months. Then, when the contempt sentence is completed, he will serve the remaining sentence for the terrorism charge and be deported.

Al-Arian pleaded guilty in April to one count of aiding the PIJ. Prosecutors had accused him of being an active member of the terrorist group, but a six month trial in 2005 failed to produce a guilty verdict.

This is the second hunger strike for Al-Arian. he started the first one shortly after he was arrested in February 2003 and continued for 140 days, his supporters say. Jail officials said Al-Arian drank Carnation Instant Breakfast during that hunger strike because he has diabetes and required nutrition along with his medication.