A pensioner and her 25-year-old son have been released on bail after they were arrested on suspicion of encouraging or assisting a suicide.
A Sussex Police spokesman said: "It is an offence to encourage or assist suicide under the Coroners and Justice Act 2009 and officers are investigating whether any crime has been committed or is likely to be committed if they do not take action."
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The former prime minister made the comments as he prepares to return to politics saying he wants to be "part of the debate" on Brexit.
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