Pakistan was in a state of high alert Wednesday over fears terrorists could mark the first anniversary of Osama bin Laden’s killing by American Navy SEALs with revenge attacks.

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

Its dubious reputation has been dragged deeper through the mud and its relationship with the United States is as bad as ever as questions on Islamabad’s intelligence failures or complicity with Al-Qaeda remain unanswered.

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

A year after the Al-Qaeda terror chief was found living with three wives on the doorstep of Pakistan’s equivalent of West Point, the country is still accused of sheltering a string of America’s most-wanted terror suspects.

Ayman al-Zawahiri, bin Laden’s successor, is suspected to be in Pakistan, as is Afghan Taliban leader, Mullah Omar.

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 Hafiz Saeed, the Pakistani accused of masterminding the 2008 Mumbai attacks who lives openly in Pakistan, a bounty eclipsed only by the $25 million reward for Zawahiri.

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

The beheading of a British aid worker in Quetta at the weekend, for which there has been no claim or clear evidence pointing to the culprits, served as a reminder of the dangerous underbelly of Pakistan. (AFP)