An old but scary article about life in Tehran. Another & more extensive article on the same subject can be found here.
Dogs are considered unclean in Islamic law and the spread of dog ownership in Westernised secular circles in Iran is frowned upon by the religious establishment.
"I demand the judiciary arrest all dogs with long, medium or short legs - together with their long-legged owners," Hojatolislam Hassani is quoted as saying in the reformist Etemad newspaper.
"Otherwise I'll do it myself," said the outspoken cleric, who leads Friday prayers in the north-western city of Urumiyeh.
"In our country there is freedom of speech, but not freedom for corruption," he said.
Tehran journalist Mafiseh Kouhnavand told the BBC that the subject of dog ownership had been brought up many times before.
Hardline judiciary agents and police occasionally clamp down on the practice, fining owners and confiscating their pets from streets and parks.
In June, police banned the sale of dogs and penalised anyone walking a dog in public. The practice is seen by conservatives as a corrupting influence of decadent Western culture.
But despite the clampdowns, dog ownership has been on the rise, especially among rich Iranians in the north of Tehran.
"Now it has reached Urumiyeh, but some people were not ready for it," Ms Kouhnavand said.
Hojatolislam Hassani appears to be widening the scope of his anti-canine campaign.
Last year, he publicly thanked police for their policy of exclusively confiscating short-legged dogs in Urumiyeh.