Updated

Two men have been injured by a small explosion at an anti-government protest site in Bangkok.

Erawan emergency medical services said the men were hurt Saturday following an explosive sound behind the stage at the protest site in northern Bangkok.

According to Thai journalists' postings on Twitter, two grenades from an M79 exploded at the site shortly before 8 p.m. The perpetrators are not known.

The protesters are seeking to have caretaker Prime Minister Yingluck Shinawatra step down to make way for an interim appointed government to implement what they say are necessary reforms to fight corruption. They've been protesting since November and have battled police on several occasions.

At least 10 people have been killed and scores hospitalized in connection with the political unrest.