New Delhi: Police on Thursday arrested four men in India’s technology hub of Bengaluru over a video recording of a New Year attack on a woman that has sparked a national public debate about women’s safety.

News of the video came after a Reuters witness and media said several women revellers were groped and assaulted by a mob in the southern city in a separate incident on New Year’s Eve.

Police made the arrests after examining a closed-circuit video clip of the attack by two men as the woman walked down a secluded lane in a residential area late on Dec. 31.

The four men arrested were ‘directly related to the case’, including the two who perpetrated the attack, a senior city police official said.

‘There is clear evidence in the case,’ added the official, who declined to be named as he was not authorised to speak to the media.

The police official did not elaborate on why the other two men were arrested. All face charges of sexual harassment and assault.

The video sparked outrage because it showed a man dismounting from a scooter to grab the woman and drag her towards the vehicle, despite her struggles. The other man on the scooter briefly joined the scuffle as bystanders watched.

But she was thrown to the ground before the men rode off.

Bengaluru, in India’s southern state of Karnataka, is home to many well-educated professionals, and had widely been viewed as safer for women than New Delhi, which is often labelled the country’s rape capital, for the many sex crimes reported there.

Sex crimes are common in India, with more than 34,000 rapes reported in 2015, figures from the National Crime Record Bureau show.

Authorities often face criticism for not doing enough to address a weak system of law enforcement and policing that leaves women vulnerable.

G. Parameshwara, the state’s home minister, said the government would soon bring the ‘culprits to book’.

The government plans to install nearly 550 more closed-circuit cameras within two months, increase police call-centre facilities and deploy more women police officers, he added.