Leading human rights activist Nabeel Rajab has been detained in Bahrain, four months after he was completed a two-year prison sentence.

Rajab was seized after remarks on Twitter “deemed offensive to the security forces”, the Interior Ministry said.

The Ministry said, “Legal measures have been taken to refer him to the general prosecution” because he “insulted official bodies in his tweets”.

The prosecution later said Rajab will be detained for seven days during investigations.

On Sunday, Rajab alleged that Bahrainis joining the Islamic State’s jihadists in Syria were originally members of Bahraini security forces: “Many #Bahrain men who joined #terrorism & #ISIS came from security institutions and those institutions were the first ideological incubator.”

Rajab, the President of the Bahrain Centre for Human Rights, has been detained on numerous occasions since mass protests for rights and reforms began in February 2011. He was finally sentenced to three years for his leadership of demonstrations and his remarks on Twitter, with his prison stay later reduced to two years.