Islamist protesters demanding Bangladesh have a blasphemy law clashed with secularists and students, who organised their own protest in response.
The initial rally, attended by hundreds of thousands of people, was organised by Hifazat-e Islam activists, who demanded atheist bloggers who insult Islam be hanged.
Secularists tried to disrupt the protesters reaching the capital Dakar by calling a 22-hour nationwide strike.
More than a dozen people were been injured as the Islamist protesters fought with the secularists and students, and as each group clashed with the police.
The bloggers accused of insulting Islam say are seeking capital punishment for those found guilty of war crimes during the nation’s 1971 independence war against Pakistan.