Social media postings show at least five women in Iran protesting the obligatory Muslim headscarf by taking theirs off and waving them on sticks.
The videos and photos showed individual women in separate locations in Tehran and Isfahan.
Masoud Sarabi, who witnessed one of the protests on Monday, confirmed the authenticity of a video shot on Tehran's Enghelab Street.
The others appeared to be authentic, but The Associated Press could not independently verify them.
The women appear to be following the lead of a 31-year-old protester identified as Vida Movahed, who took off her headscarf on the same street in late December.
She was detained for a few weeks and then released.
Women showing their hair in public can be jailed for up to two months or fined $US25.
The Islamic dress code, in place since the 1979 revolution, considers Islamic veiling or hijab, obligatory for any female above 13 in Iran and says they should cover themselves from head to toe while disavowing any figure-hugging dress.
In late December, police said they would no longer arrest women for failing to observe the code.
The announcement signalled an easing, as called for by the young and reform-minded Iranians who helped re-elect President Hassan Rouhani, a relative moderate, earlier this year.
Many Islamists believe hijab should not be imposed by the law, though they consider it a religious task for every Muslim woman.
