CAIRO: Egyptian prosecutors have detained a satirist known for his ribald humour on suspicion of joining an "illegal group", his lawyer told AFP Tuesday.

Islam al-Rifai, who has more than 70,000 followers on Twitter were he posts lewd jokes and pictures, was arrested last Thursday, his lawyer Gamal Eid said.

Eid said Rifai, who also designs websites, had been lured into being arrested after receiving a phone call from someone who claimed he wanted his help with a website.

Prosecutors then charged him with belonging to an "illegal group", the lawyer said.

It was not immediately clear what group prosecutors suspected him of joining.

Rifai's arrest led to supporters launching Twitter hashtags reading in Arabic "Freedom for Khorm" and "Khorm is not a criminal", a sexually suggestive alias he used that literally means "hole".

President Abdel-Fattah al-Sisi, a former military leader elected after ousting his Islamist predecessor, has been accused of a widening crackdown on dissent.

Sisi, who remains popular with many Egyptians who say the country needs a firm hand after years of tumult, is expected to stand in and win another election next year.