Bangkok, Thailand (CNN) -- Two explosions rocked an anti-government protest in the Thai capital of Bangkok on Friday, wounding more than two dozen people, security and health officials said.
The blasts went off as protesters were marching in the streets, said Lt. Gen. Paradon Pattanathabut, the national security chief. The cause wasn't immediately clear.
Twenty-eight people were wounded and taken to hospitals, according to the Erawan Emergency Center, a medical unit monitoring the political unrest in Thailand.
Demonstrators demanding the resignation of Prime Minister Yingluck Shinawatra began their latest round of rallies -- dubbed the "Bangkok shutdown" -- in the capital Monday. But their numbers have shrunk over the course of the week.
Explosions hit Thai anti-government protest in Bangkok; 28 injured