Iranian police were on patrol in Tehran yesterday on alert for any further violent protests over the introduction of petrol rationing in the world’s fourth largest oil producer.

A dozen petrol stations were set ablaze in violence that erupted late Tuesday and angry motorists queued for hours throughout Wednesday to fill up their tanks after the government’s sudden announcement.But yesterday, state-run television said the streets were calm and no further trouble had been reported near petrol stations despite long lines of cars still waiting at the pumps.“The situation in the city is calm and the police are patrolling the city’s main roads and squares,” Tehran metropolitan police spokesman Mahdi Ahmadi was quoted as saying by Iran’s energy news agency Shana.“Thank God there was not any report of any kind of unlawful act in Tehran last (Wednesday) night.”

The hardline Kayhan newspaper, a staunch supporter of President Mahmoud Ahmadinejad’s policies, hailed the rationing move and blamed a “petrol smuggling mafia” for the violence.“Petrol rationing means people can enjoy public treasury money more justly,” the paper said.

Motorists vented their anger over the rationing move, which came into effect just hours after an official announcement, with some protestors shouting slogans against Ahmadinejad. It was the first such open outpouring of anger since Ahmadinejad took office in 2005.