By Aamer Ahmed Khan
BBC News, Karachi
Three papers have been banned for publishing "hate material" in the Pakistani province of Sindh.
Friday Special is one of several papers published by Islamic parties
The periodicals are the first to be outlawed in President Pervez Musharraf's crackdown on provocative religious material.
The crackdown came soon after the London bombings which killed 52 people and injured around 300 more.
The three periodicals banned by the Sindh government are Zarb-e-Islam, Wajood and Friday Special.
Mohammed Tahir, the editor of Wajood, has been arrested and remanded in custody.
The associate editor of Friday Special, Abdul Latif, was also arrested but later released on bail.
Mr Tahir told the BBC News website that he was arrested by policemen in plainclothes who said his paper was writing against Gen Musharraf's government.
"They never mentioned anything about hate material," he said.
The editor of Friday Special, Yahya bin Zakria, said that the ban on his paper was aimed at silencing a vociferous critic of the government.
Friday Special is one of several publications published by associates of Jamaat-e-Islami, an Islamic fundamentalist party.
"We will employ all legal means to resist such attempts at gagging the press," Mr Zakria said.
He said he would raise the issue with the All Pakistan Newspaper Society (APNS) - Pakistan's leading press owners' association.
Qazi Asad, APNS secretary general, said the organisation had not yet been formally notified about the banned periodicals.
"We have to examine the grounds on which their declarations were cancelled before we can form an opinion," he said.
Officials said these publications were banned on the recommendation of the home department and the city police chief.
The two said in separate appraisals that the content was instigating hatred and violence among people of different sects.
Home department officials said 13 publications based in the southern province of Sindh are on a watch-list.
Officials in Punjab are also said to be monitoring another 20 publications.