A timeline of recent blasts in Bangkok

[BANGKOK] At least 19 people were killed and more than 120 injured when a bomb exploded on Monday outside a religious shrine in the Thai capital, in its deadliest single assault in recent years.

The explosion came at a time of heightened political tension in the deeply divided nation.

Thailand's long-running political conflict broadly pits a Bangkok-based middle class and royalist elite, backed by parts of the military and judiciary, against rural and working-class voters - many of whom are part of the Red Shirt movement - loyal to ousted former premier Thaksin Shinawatra.

Martial law was imposed for several months following a coup last year that toppled the civilian administration. It has since been lifted but the junta retains sweeping security powers.

Small bomb blasts occur in the capital during times of heightened tension - with all factions accusing each other of resorting to violence.

However none have been on the scale of Monday's attack, for which no-one claimed responsibility, and it was not immediately known if it was linked to the political tensions.

Here is a brief timeline of other main bomb attacks in Bangkok over the past five years.

2010

April: Five grenade blasts hit Bangkok, targeting hundreds of pro-government supporters in attacks that leave one dead and scores wounded, including foreigners. The grenade blasts come after a failed attempt by authorities to disperse the Red Shirts, sparking clashes that left 25 people dead and more than 800 injured in the worst civil unrest in almost two decades.

July: The government says a bomb that killed one at a bus stop in central Bangkok was designed to create disorder.

September: Bangkok put on high alert after a series of grenade blasts. Thousands of police and soldiers are mobilised for extra security.

October: A blast at an apartment complex kills four, with the government blaming the incident on the anti-government "Red Shirt" movement. The Reds deny any involvement and accuse the authorities of a plot to justify tougher security powers.

November: A grenade is thrown onto a minibus killing one. It was not clear if it was politically motivated.

2011

January: Police arrest five men armed with explosives after a tip-off that bomb attacks were planned near the seat of government in Bangkok.

June: Two people are injured in a blast at a political protest by Thailand's "Yellow Shirt" demonstrators near Government House.

December 7: A makeshift explosive device is found and defused near the government lottery office with authorities saying the perpetrators wanted to "challenge the government".

2013

May: A homemade bomb hidden near rubbish bins in a busy suburban Bangkok shopping area explodes, injuring seven people.

2014

January 18: One protester dies after a bomb attack at an opposition march in Bangkok. Authorities and demonstrators blame each other for the blast, which was apparently caused by a grenade-type device thrown from a nearby building.

January 19: Twin blasts by unknown attackers at an anti-government protest in central Bangkok leave 28 injured.

2015

February: Two small bombs explode near a popular shopping mall in downtown Bangkok. One man is injured but there are no deaths.

August 17: At least 16 people - among them foreigners - are killed after a blast in Chidlom district at a popular shrine located on a main road through Bangkok's commercial hub.

AFP