A cartoon in Friday's edition of Iran newspaper had depicted an ethnic Azeri as a cockroach, sparking clashes between police and thousands of people in the main northwestern city of Tabriz.
"Fifty-four people have been arrested from the ones identified yesterday for vandalism," Tabriz prosecutor, Yusef Firoozi, was quoted as saying by the student ISNA agency.
"They have all had police records and the rest of those identified will be arrested soon."
A local intelligence ministry official, identified as Valizadeh, told ISNA: "the ones inciting unrest and vandalism yesterday were all supported by foreigners and were linked with issues in Khuzestan".
The oil-rich southwestern province of Khuzestan has an Arab majority and has been seen a series of bombings in the past year.
Valizadeh also accused the United States and Israel of seeking to incite ethnic disputes in Iran.
"Now that we are more united than ever, American and Israeli intelligence services have put Iran's ethnic issues on the agenda. Exploiting yesterday's move was in line with that," he was quoted as saying.
The Iranian government's official national newspaper was banned Tuesday, and two of its journalists arrested for publishing the cartoon.
"This ban is because it published material which provokes divisions among people. It is banned, and its case has been sent to the press court," said Hassan Kamran, a member of Iran's press supervisory committee.
He told ISNA that the paper would not be published again until a verdict on the case was issued by a special tribunal dealing with press offences.
Tehran's hardline chief prosecutor, Saeed Mortazavi, told state television that the cartoonist and page editor -- Mana Neyestani and Mehrdad Qasemfar -- had been arrested and taken to Tehran's Evin prison.
He said the publisher of the paper would also be prosecuted.
Press reports said that thousands of ethnic Azeris in Tabriz had gathered outside the office of the governor of East Azerbaijan province on Monday.
Etemad-Melli paper said police used tear gas to disperse the crowd after some protesters pelted security forces with stones, injuring several policemen.
Interior Minister Mostafa Pour-Mohammadi told the official IRNA news agency that publication of the cartoon was "an insult to all Iranians, and we cannot tolerate that".
The Iran newspaper -- which is published by IRNA -- has already made a formal apology and said the cartoonist has been sacked.
Ethnic Azeris, concentrated in northwestern Iran, account for some 25 percent of the population and are far more numerous in Iran than across the border in former Soviet Azerbaijan.
The hardline newspaper Kayhan blamed foreigners for inciting the ethnic unrest. "Our fellow Azeri countrymen are too clever to be exploited by Iran's sworn enemies in their plots," the paper said.
The Iran daily is not the first to run into problems this year.
A weekly publication in southern Iran was shut down permanently in April for "insulting the Islamic republic's leadership".
In March, another local weekly published in Iran's ethnic Azeri provinces was closed on charges of ethnic bias and of acting against national security.
Between 2000 and 2004, Iran's hardline judiciary shut down a large number of mostly reformist newspapers and magazines, and jailed scores of journalists.
05/23/2006 14:58 GMT
