Nigeria is among a group of nations categorized as "high risk" in the latest World Terrorism Risk Index.

Placed on the 19th position, the country is viewed as high risk terror destination. Britain is placed at 47, behind the US at 33 and France at 44, but all remained in the "medium risk" category, while Canada (67) and Germany (70) were rated as "low risk".

According to the 2010 version of the Maplecroft report 16 Countries have been categorised as "extreme risk" including in the following order of high risk: Somalia, Pakistan, Iraq, Occupied Palestinian Territories, Colombia, Thailand, Philippines, Yemen, Russia, Lebanon, Sudan, DR Congo, Israel, India and Central African Republic.

Somalia has overtaken Iraq, Afghanistan and Pakistan to become the country most at risk in this year's Terrorism Risk Index (TRI), developed by global risks advisory firm Maplecroft.

Data from June 2009 to June 2010 was used to assess the frequency of terrorist incidents and the intensity of attacks in 196 countries, including the number of victims per attack and the chances of mass casualties occurring.

The index also includes a historical component assessing the number of attacks between 2007 and 2009 and looking at whether a country is at risk from a long-standing militant group operating there.

Sixteen countries are rated as "extreme risk" with Pakistan at 2, Iraq 3, Afghanistan 4, Palestinian Occupied Territories 5, Colombia 6, Thailand 7, Philippines 8, Yemen 9 and Russia 10.

Somalia experienced 556 terrorist incidents between June 2009 and June 2010, in which 1,437 people were killed and 3,408 wounded.

It has the highest number of deaths from terrorism per population and surpassed Iraq and Afghanistan in the number of fatalities per terrorist attack.

The principal threat in Somalia comes from the Islamist al Shabaab, which has claimed responsibility for several deadly suicide bombings.

In February last year, 11 Burundian soldiers on an African Union peacekeeping mission were killed in a blast.

The group carried out its first major international attack in July 2010 when it bombed the Ugandan capital, Kampala, killing at least 74 people.

Yemen moved 13 places in the ranking and into the 'extreme risk' category for the first time.

The country has seen a significant increase in the number of terrorist incidents on its own soil, with a total of 109 attacks between June 2009 and June 2010.

Yemen's primary source of terrorism is al Qaeda in the Arabian Peninsula (AQAP), which is causing growing concern among Western intelligence services as the group plots more attacks abroad, the study said.

It was behind the printer cartridge bombs hidden on cargo planes on route to the US from Yemen last month.

Greece moved from 57 to 24 to overtake Spain (27) and become the European country most at risk from terror attacks. Between June 2009 and June 2010, the country experienced 180 attack.