The protest came two days after masked attackers went on a rampage inside the campus of the prestigious Jawaharlal Nehru University (JNU)
One of Bollywood's top stars sparked a social media storm on Wednesday, attracting admiration and vitriol after showing solidarity with students who were attacked at a Indian university this week.
Indian film stars have traditionally shied away from politics, fearing their films could be boycotted or their safety threatened.
The industry also relies heavily on government support.
But Deepika Padukone, 34, the country's top-earning female celebrity according to Forbes India, broke the mould when she attended a demonstration in New Delhi on Tuesday evening.
The protest came two days after masked attackers went on a rampage inside the campus of the prestigious Jawaharlal Nehru University (JNU), leaving 34 students and faculty members injured.
Police reportedly stood by and did nothing, while videos purportedly from the scene showed masked men swinging batons as students screamed in terror. No-one has been arrested in connection with the violence.
The incident has been blamed on the Akhil Bharatiya Vidyarthi Parishad (ABVP), a student body linked to Prime Minister Narendra Modi's ruling Bharatiya Janata Party. The group denied involvement.
Padukone's appearance led to calls -- including from BJP spokesman Tajinder Pal Singh Bagga -- for her upcoming film Chhapaak to be boycotted, while others accused her of a publicity stunt ahead of its release on Friday.
"It is said Bollywood doesn't take a stand," Advaita Kala, a screenwriter and commentator, said on Twitter.
"@deepikapadukone has decided to take a stand with the Leftist students at JNU. She shd be informed that ABVP students have also been injured. Rather than a partisan approach, wish she'd used her celebrity to build a bridge between students," Kala added.
But others jumped to her defence, calling for people to go and see her movie in solidarity, leading to a battle of hashtags including "#ISupportDeepika" and "#boycottChapaak".
"The female of the species is, and was, and will always be the strongest of the two #DeepikaPadukone," tweeted Anurag Kashyap, a leading Bollywood director.
"Let's all those who stand against the violence go to @bookmyshow and show them. Make our silent statement which will be the loudest," Kashyap added.
"We are proud to see so many voices from the film industry take the lead. More power to you @deepikapadukone. Bravo!! #ISupportDeepika," the youth wing of the main opposition Congress party tweeted.
The violence at JNU is the latest in a series of clashes that have killed at least two dozen people amid protests over a controversial new citizenship law Modi's government passed in December.
It speeds up citizenship claims from persecuted non-Muslim minorities from Pakistan, Afghanistan and Bangladesh, stoking fears that Modi wants to marginalise India's Islamic minority, which he denies.