Cellphone services in several major urban areas in Pakistan resumed Monday after a 14-hour blackout over concerns of a possible terrorist plot to coincide with the end of the Muslim holy day of Ramadan, news services said.

Pakistani Interior Minister Rehman Malik ordered services providers to shut down their networks in the southern city of Karachi, the eastern city of Lahore, the central city of Multan and the western city of Quetta around 8:00 p.m. Sunday (11 a.m. ET Sunday) because of concern that cellphones could be used to detonate explosives, Pakistan's Geo News reported.

On Sunday, Pakistan -- and Muslims worldwide -- celebrated Eid-ul-Fitr, which marks the end of Ramadan. It is traditionally a time when Muslims reach out to connect with relatives on the holiday.

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Karachi, with around 13 million residents, is Pakistan's largest city. Together the four cities affected boast a population of more than 22 million people.

Malik said the government had been monitoring terrorist threats in several areas on Sunday, Geo news said. Malik said possible terrorist plots were uncovered in Punjab province, of which Lahore is the capital. 

"The cellular service would be suspended in a surprise manner in the sensitive parts of the country; however, timeframe could not be given," The Dawn newspaper quoted Malik as saying.

Malik also apologized for any inconvenience caused by the blackout.

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During the effective blackout, parts of Karachi, Lahore and Multan still had partial service. However, cellphone service was suspended completely in Quetta.

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Network providers turned their services back on Monday after the Interior Department gave them the go-ahead, Pakistan's The News, citing unidentified sources, reported.

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Malik initially said that services would be allowed to resume at 10:00 a.m. Monday (1 a.m. ET Monday), although it was not immediately clear precisely when services were switched back on.

Slideshow: Pakistan: A nation in turmoil

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Images of daily life, political pursuits, religious rites and deadly violence.

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Problems with extremism
Pakistan has suffered from a number of terrorist incidents in recent years and the cities affected by the cellphone blackout have been wracked with violence. Parts of the country have also been hotbeds of Islamist extremism.

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Various groups have been blamed for attacks on Pakistani security forces, as well as across the border in India and in Afghanistan, where coalition forces are often targeted by Taliban-aligned militants operating out of bases in Pakistan.

Many other militant groups operate in Pakistan, including factions fighting Indian rule in Kashmir, separatists demanding greater share of the income from generated from natural resources in various provinces, and other violent factions targeting minority Shiite Muslims.

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Police in Australia are seeking help from the FBI and Britain’s Scotland Yard after tens of thousands of Australians received death threats by text message, warning them that they will be killed unless they pay thousands of dollars, according to reports Monday.

It has commonly been referred to as "the hitman scam," according to The Sydney Morning Herald newspaper.

The Australian newspaper reported that the text message included the following line: "Sum1 paid me to kill you. get spared, 48hrs to pay [AU] $5000. If you inform the police or anybody, death is promised...E-mail me now: killerking247yahoo.com."

The Morning Herald quoted New South Wales Chief Superintendent Peter Cotter saying that state police would look abroad for help.

"We have direct connections with many international law enforcement agencies," Cotter told the newspaper.

"There'll be people we'll be speaking to, such as the FBI and London Metropolitan Police and so forth," he told the paper.

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'A very ugly attempt by fraudsters'
Queensland Police Detective Superintendent Brian Hay called on recipients to delete the messages and disregard the threat, which he said had no credibility.

"Across Australia at this point in time we've been flooded and inundated by disturbing emails and text messages claiming that you're about to be killed if you don't part with the sum of (Australian) $5,000 … to be transferred into the hands of criminals. Please understand that this is a scam -- a very ugly attempt by fraudsters overseas to get your money. There is no immediate threat to you or your family," Hay said in a video message to the public posted on the website for The Age newspaper.

The Australian Broadcasting Corporation quoted a man identified only as “Shane” as saying he did not take the threat seriously.

"I've probably got about $30 million worth of lottery text messages in my phone at the moment. So, usually when I get a message from an unknown number I don't take it too seriously," he was quoted as saying.

People in at least five Australian states -- New South Wales, Western Australia, Victoria, Queensland, South Australia and Tasmania -- have reported receiving the texts on their cellphones, The Australian newspaper said.

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