Protesters incensed by the film and inspired by influential Pakistani religious parties set fire to a motorway toll booth just outside the capital and a cinema in the northwestern city of Peshawar in images broadcast live on television.

Pakistan's government, wary of widespread frustration over its failure to provide basic services, declared Friday a day of protest over the film in an apparent bid to exploit anger which has inspired violent protests in several Muslim countries.

Critics say this approach is typical of a government that many describe as ineffective in the face of tough challenges; from a stubborn Taliban insurgency to chronic power cuts, which have frequently triggered protests.

Others said calling for the "day of Love for the Prophet" was a shrewd political move for the embattled government.

"Our heart is crying bloody tears. We can bear everything but disrespect to our Prophet and Koran," said Akbar Saeed Farooqi, spokesman for a religious organization that helped organise demonstrations.

The government can use all the help it can get. Prime Minister Pervez Raja Ashraf is under pressure from an increasingly assertive Supreme Court to reopen corruption cases against the president.

The court removed his predecessor for failing to do so.

Political strife has often distracted civilian leaders and the military, which has ruled the country for more than half of its 65-year history, is seen as the most efficient and decisive institution in times of crisis.

Many of the parties orchestrating the protests oppose Pakistan's alliance with the United States, which has only recently begun to recover from a number of setbacks.

The government's critics condemned the national holiday as a capitulation to religious rabble-rousers in a young democracy still struggling to define the place of religion in public life.

Pakistan, a nuclear-armed nation of 180 million people, is overwhelmingly Muslim. Pakistan was carved out of India as a land for Muslims in 1947.

For decades, leaders invoked Islam to legitimize their rule and politics is often influenced by religious parties who don't score big votes in polls but can whip up anger on the streets.

"All it takes is a couple hundred people and a pile of rocks and you're on TV," said Husain Haqqani, a former Pakistani ambassador to the United States. "The religious parties hold the government hostage."

"OBSESSED WITH POLITICS"

The ruling Pakistan People's Party PPP.L was set up as a centre-left, progressive party with secular leanings but, like most political forces in Pakistan, it has played to the religious parties when under pressure.

The PPP and its opponents have started jockeying for advantage ahead of a general election expected next year and that would appear to explain why it is tapping into anger fuelled by clerics over the film, instead of trying to calm it.

"The Pakistan People's Party has become so obsessed with domestic politics and getting re-elected they have forgotten what kind of relationship they want with the outside world," said columnist Mehreen Zahra-Malik.

Religious parties fared poorly in the last election. But orchestrating protests is an easy way for them to flex political muscle and ensure they can forge alliances with more powerful parties.

Lawmaker Ayaz Amir said the government had proclaimed the holiday to undercut the religious parties, an attempt to show it too has Islamic credentials.

"The government has stolen a march on them," he said.

He said it made sense for the government to try to defuse protesters' anger by giving them an outlet instead of ordering police to shut down rallies and risk alienating people.

Most demonstrations in the day's immediately following coverage of the film were small and peaceful. Few people had heard of the film.

Then religious groups began running advertisements on television demanding Muslims sacrifice their lives for the Prophet's honour. Signs went up demanding the film-maker be shot.

Once protests reach critical mass, it's dangerous for people to oppose them. In Hyderabad city, a cleric directed a mob to attack the house of a shopkeeper who had refused to join a protest, police said.

On Thursday, protesters threw stones, smashed cars and burnt a police post in the heart of Islamabad as they tried to force a path to the U.S. embassy.

Few protesters interviewed by Reuters had seen the film, yet the government seems to think it can capitalise on the mounting anger in a country where a perception the United States is out to get Muslims fuels anti-American feeling.

In a speech to dignitaries marking the holiday, Ashraf appeared to play up those fears about the West.

"This was a deliberate premeditated attack based on bias, hatred and prejudice," he said of the amateurish film. (Additional reporting by Imtiaz Shah in Karachi, Hamid Shaikh in Hyderabad and Aisha Chowdhry in Islamabad; Editing by Michael Georgy and Robert Birsel)

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