Bulgaria's Foreign Ministry has moved to increase the security measures for all its diplomatic missions abroad in the aftermath of Al Qaede leader Osama bin Laden's demise.

Tougher control will be applied on the access to Bulgaria's embassies and the packages received. Those who need the assistance of the country's diplomatic missions, will be scrutinized more thoroughly upon entering them.

"Other measures are to be taken, too," Vesela Cherneva, the Foreign Ministry's spokesperson, said Monday, without revealing further details. The Balkan nation is a US ally. Currently, its Afghanistan contingent consists of 600 troops.

The US already issued an alert to its embassies around the world, warning Americans of the possibility of Al-Qaeda retaliation attacks.

Law enforcement authorities should be extra vigilant due to the heightened terror risk from Al-Qaeda affiliated or Al-Qaeda inspired terrorists as a result of bin Laden's death, according to Interpol.

Early on Monday, Osama bin Laden was killed in a military operation in Pakistan that U.S. President Barack Obama ordered on Sunday. U.S. special forces launched a helicopter-borne assault on a closely guarded compound in Abbottabad, 30 miles north-east of Islamabad, on Sunday night, Obama and US officials explained. The late Al Qaeda leader's body was later buried at the sea.