A controversial Jersey politician who claimed officials on the island covered up child abuse is considering legal action against police after he was arrested.

Whistle-blower Stuart Syvret was arrested yesterday in connection with an alleged breach of data protection law.

The 43-year-old senator was not charged and, after a day in custody, was released “pending further inquiries”. He said officers searched his home and he was kept in a cell all day, other than for a two-hour interview.

He claims police did not have a warrant to search his property and believes the arrest was politically motivated. He said: “The whole exercise was designed to intimidate and harass me and to intimidate the whistle-blowers who give me information.

“I am going to seriously contemplate a legal action of my own because of this. This is what happens to anyone on Jersey who rocks the boat — you get clobbered.”

Syvret was an outspoken critic of the establishment’s handling of the historic police investigation into child abuse on the island and in 2007 he was dismissed from his post as Minister for Health and Social Services after claiming abuse cases were being covered up.

The investigation focused on the Haut de la Garenne children’s home where hundreds of former residents claimed they were sexually and violently assaulted.

Syvret, who called for both an independent inquiry and for court cases to be held on the UK mainland, was accused by the Chief Minister Frank Walker, of damaging Jersey’s reputation.

He said: “The police said they are releasing me, that they are not charging me, but that I am still under investigation. The whole thing is politically motivated — the police would not have undertaken this action spontaneously.”

Following the arrest, Liberal Democrat MP John Hemming said he had sent a letter to Justice Secretary Jack Straw asking him to monitor the situation because he believed it could be “motivated by political reasons”.

Mr Hemming said: “Senator Syvret has recently revealed detailed evidence relating to a nurse in Jersey who may have murdered a number of patients.

“He has also been working with me to try to get the rule of law to operate in respect of the investigations into child abuse in children’s homes on Jersey.”

A Jersey police spokeswoman said they could not comment directly on Syvret’s accusations that they had acted illegally. She said: “A 43-year-old man has been released pending further inquiries.”

The child abuse inquiry was dogged by controversy from the outset, with claims that the island’s government was obstructing the police and claims by the government that the police had mishandled the inquiry.

In November last year Lenny Harper, the Londonderry-born detective heading the inquiry, announced his retirement and then slammed the island’s legal system, claiming it delayed prosecutions and was held in “contempt” by victims.

Mr Harper claimed his team would put together a case file but would run into “inexplicable delays” and they felt like “the goalposts were being moved”.