ISLAMABAD: Pakistan was in a state of high alert Wednesday over fears militants will launch revenge attacks on the first anniversary of Osama bin Laden's killing by American Navy SEALs.

The anniversary of the single most humiliating event in recent Pakistani history caps a devastating year for the country.

Apart from the breakdown of its alliance with the West, little has changed.

US says Ayman al-Zawahiri, bin Laden's successor and Afghan Taliban leader, Mullah Omar might be in Pakistan.

Sirajuddin Haqqani, the de facto leader of the Haqqani network blamed for last month's assault on Western targets in Kabul -- the largest coordinated insurgent attack in 10 years of war -- is based in the tribal belt on the Afghan border, as is Pakistani Taliban leader Hakimullah Mehsud.

Last month Washington offered $10 million for information leading to the arrest and conviction of Hafiz Saeed, the Pakistani accused of masterminding the 2008 Mumbai attacks who lives openly in Pakistan.

Pakistani officials told AFP they fear attacks could mar the anniversary, saying that security agencies had been ordered to be "extra vigilant" on Wednesday.

Last year, the Taliban carried out a string of revenge attacks that included a suicide bombing on a police training centre that killed nearly 100 people.

"These agencies are in a state of high alert and have been directed to be very careful since this is going to be an important day," one security official told AFP on condition of anonymity.

Western embassies in Islamabad issued warnings, advising citizens to avoid public places for fear of attack. The US embassy has restricted staff from going to restaurants and markets until May 5.

But Pakistani authorities have tried to ignore the anniversary and erase all trace of bin Laden, who lived in the country from December 2001 until his death last May, according to testimony from his widow Amal Abdulfattah.

She was deported to Saudi Arabia on Friday along with bin Laden's other two widows and 10 children.

There was no extra police or military presence at the site of the house in Abbottabad where bin Laden spent six years, which was bulldozed in the dead of night in February.

A local police official told AFP he had been given no special instructions and locals were keen to move on.

"The Osama issue should be dead now. No anniversary should be observed as any event on this day every year will trigger new controversies," said 35-year-old Omar Zada, a mason.

In neighbouring Afghanistan, the Taliban attacked a heavily-fortified guesthouse complex used by Westerners, killing at least seven people on Wednesday just hours after US President Barack Obama marked the bin Laden anniversary by slipping into Afghanistan to make an address from Bagram air base.

But US-Pakistani ties are still deeply troubled. Islamabad closed NATO supply lines into Afghanistan five months ago over the killing of 24 soldiers in US air strikes and it remains unclear whether Pakistan will attend this month's Chicago summit on Afghanistan.

To American disappointment, a commission tasked with getting to the bottom of the bin Laden debacle is yet to publish its findings and has even questioned whether he was definitely killed in the raid. -- AGENCIES