Bangkok: A bomb blast at an opposition protest march in Bangkok wounded at least 28 people, emergency officials said on Friday, in the latest unrest during a "shutdown" of the capital aimed at ousting the government.
"The latest figure we have is 28 injured," said an official from the city's Erawan emergency centre, in an updated figure.
She said there were no details of how serious the injuries sustained were.
Police were investigating what type of explosive device caused the blast.
Television footage showed several people lying on the ground as ambulances rushed away the wounded.
Protesters were seen searching nearby buildings for the attackers as police and soldiers arrived on the scene.
"The bomb went off shortly after 1 pm (0600 GMT)," deputy national police spokesman Anucha Romyanan said.
The blast is the latest attack on opposition protesters who have blocked roads and held rallies across the capital in a bid to topple the government of Prime Minister Yingluck Shinawatra and derail upcoming February 2 elections.