The warning came after the US State Department put out a travel alert and closed 21 of its embassies in response to non-specific information suggesting that al-Qaeda is planning terror attacks in August.

In a statement issued from its general secretariat HQ in Lyon, France, Interpol urged countries around the world to show "increased vigilance", following prison escapes over the past month which freed hundreds of terrorists in nine nations including Iraq, Libya and Pakistan.

Britain announced it is shutting its embassy in Yemen for two days because of security concerns.

The CIA is said to have collected and analyzed electronic communications between senior al-Qaeda figures last week which pointed to the potential for attacks to take place in North America and the Middle East.

Concerns about spread of terrorist attacks by extremists were already high in the Middle East due to massive support by the US and its allies to different groups of militants pouring to Syria to topple the government of Syrian President Bashar al-Assad.

On June 28 The Wall Street Journal reported that the US intelligence agency will continue mobilizing arms, including anti-tank missiles, in Jordan for three weeks to lay the ground for an August assault on Syria which has been gripped by war since March 2011.

SHI/SHI