Thai Prime Minister Prayuth Chan-ocha has ordered security to be tightened in Bangkok after two pipe bombs rattled a luxury shopping mall and stoked tension in a city under martial law since a coup last May.

Two people were slightly hurt but the blasts caused little damage on Sunday evening. They were the first to shake the capital since the military seized power to end months of sometimes deadly street protests.

"I have ordered security to be tightened because this case involves the well-being of the people," Prayuth told reporters on Monday.


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"This case shows that we still need martial law ... there are still bad people disrupting the peace. We must find ways to severely punish them."

There was no claim of responsibility.

They did not aim to cause major damage ... they were used to create trouble.

 Prawut Thavornsiri, national police spokesman

A team of forensic police on Monday sifted through the debris created by the blasts, which struck at around 8pm local time (13:00 GMT) on Sunday on a walkway leading to the busy Paragon shopping centre in central Bangok.

"They were pipe bombs ... low pressure explosive devices," national police spokesman Prawut Thavornsiri said. " They did not aim to cause major damage ... they were used to create trouble."

CCTV footage showed two possible suspects near where the pipe bombs exploded, but the images were unclear and the individuals had not been identified, police said.

Defence Minister Prawit Wongsuwan said such violence "inflicts loss of confidence" in the country, where tourism accounts for about 10 percent of the economy.

Political tension has been high since last month when a national assembly hand-picked by the junta banned former Prime Minister Yingluck Shinawatra from politics for five years.

The decision angered supporters of Yingluck and her self-exiled brother, Thaksin Shinawatra, although there has been little sign of a return to the protests that have dogged Thailand for years.

Source: Reuters And AFP