Kampala - Uganda has arrested a prominent academic for criticising the wife of President Yoweri Museveni on social media, police said Saturday.Stella Nyanzi criticised Janet Museveni, who is education minister, on Facebook after the government reneged on a campaign pledge to supply free sanitary pads to schoolgirls struggling to afford hygiene products.Police spokesperson Emilian Kayima confirmed that Nyanzi was taken into custody on Friday and would appear in court Monday in Kampala on charges of cyber harassment and offensive communication under a 2011 law governing computer misuse."She kept posting issues, fighting battles on social media which we think does not serve her interests or ours," Kayima said.Last Monday, Janet Museveni said in a rare TV interview that she had "forgiven" Nyanzi, whose work specialises in the study of sexuality in Africa.The academic, whose no-holds-barred work is seen as provocative in some circles of a largely conservative society, had accused the first lady of being "totally out of touch with the reality of the masses".After Janet Museveni said the sanitary pads pledge would not be met on budgetary grounds, Nyanzi began a high profile fundraising campaign on the issue.Social media critic Rosebell Kagumire said that, with Nyanzi's arrest, "I think the government are looking for ways to extend traditional methods of intimidation to online speech. They are trying to control a space they have no ability to control".Maria Burnett, Senior Africa Researcher at Human Rights Watch, criticised the arrest as an attack on free expression."The arrest and criminal charges brought against Dr Nyanzi are yet another clear indicator that those who express critical views of the government can face its wrath," Burnett said."The manner of Nyanzi's arrest on Friday was more about intimidation than law enforcement," she added.