Six bomb blasts have wounded at least four people in Bangkok as Thailand hosts US Secretary of State Mike Pompeo at a high-profile summit, Sky News reports.
Explosive devices were found or detonated at various locations, including two at stations of the city's elevated Skytrain rail system.
The first explosions were heard just before 9am local time on Friday near the centre of the Thai capital.
Three of the injured were women who were cleaning the street, and a fourth person was hurt after a device went off at one of Bangkok's tallest buildings - the 77-storey King Power Mahanakhon building.
Erawan Medical Centre said none of victims were seriously hurt.
Six devices in total were detonated and another was recovered before it went off, said Colonel Kamtorn Uicharoen from Bangkok's police force.
Government spokesman Narumon Pinyosinwat said Prime Minister Prayuth Chan-ocha had ordered an investigation.
"The situation is being closely monitored and security measures have been tightened. The public is urged not to panic," he said.
The PM tweeted: "I would like to condemn those causing the situation which destroys peace and damages the country's image."
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