New Delhi, Feb 23 (PTI): Yashpal Singh, one of the three lawyers caught on camera thrashing journalists and JNU teachers and students at Patiala House court complex last week, was arrested tonight amid mounting outrage over alleged police inaction against those involved in the assault.

The arrest came a day after a news channel aired a sting operation in which the lawyer was seen boasting about beating JNUSU president Kanhaiya Kumar, charged with sedition, when he was brought to the court on February 17.

A senior Delhi Police official said Singh has been arrested in connection with two cases of assault when he presented himself to the investigators at Tilak Marg police station responding to summons.

Singh was caught on camera beating journalists and JNU students and teachers along with his colleagues Vikram Singh Chauhan and Om Sharma among others.

While Sharma was arrested on Saturday and subsequently released on bail, Chauhan, who led two brazen attacks, is yet to respond to multiple notices issued by the police asking him to join probe.

Groups of lawyers led by Chauhan had thrashed journalists and JNU students and teachers on February 15 and repeated their act on February 17 against Kumar and some journalists, in open defiance of Supreme Court instructions.

"While one case against Singh pertains to the February 15 incident, the other relates to the attack which took place two days later," the senior official said.