World-renowned Bahraini activist Nabeel Rajab has been arrested and jailed over Twitter remarks allegeding the kingdom’s soldiers are fighting with the Islamic State (also known as Isis).

Rajab, who is president of the Bahrain centre of human rights (BCHR) and was freed in May 2014 after serving two years in prison for his role in the pro-democracy uprising. Bahrain’s public prosecution said the activist was charged with publicly “insulting a public institution” on the microblogging site.

Earlier, the Bahraini ministry of interior announced they summoned Rajab “to interview him regarding tweets posted on his Twitter account that denigrated government institutions”. An associate writing on Rajab’s Twitter account in his absence, said: “The Public Prosecution has ordered the detention of Nabeel for 7 days on pending investigation.”

The tweets related to an article published on Global Voices about alleged Bahraini recruits to Isis who featured in a video threatening to overthrow the al-Khalifa regime the rules Bahrain. The activist commented:

The video included Lieutenant Mohamed Isa Al-Binali, who had defected from the army.

Hours before his arrest, Rajab told IBTimes UK that he received a phone call from the Criminal Investigation department and was “waiting for written summons in order to go”.

“I have no idea why they’re calling me but normally is about Twitter or Facebook,” he told IBTimes UK.

Rajab spoke to IBTimes UK in July about his time in prison and accused the British government of supporting the bloody al-Khalifa regime in the Gulf Kingdom despite daily human rights violations because of business interests.

He said that told IBTimes UK that the Bahraini government “have bought the silence of the British government by increasing the business” since the start of the crackdown on peaceful protesters in 2011.

“The arms trade has increased, the business between the UK government and Bahrain has increased after the crackdown over 30% ,” he said. “That’s why you see not only silence in the British government but also harassment to human rights defenders and even to the people living in this country and who came seeking asylum from Bahrain.”

Rajab, one of several pro-democracy campaigners arrested in the regime’s clampdown, was considered a prisoner of conscience by Amnesty International.