Cricket Australia apologised to the India team, on Sunday, and launched a probe into allegations visiting players were subjected to racial abuse by part of the crowd during the third test at Sydney Cricket Ground.
The Indian team lodged an official complaint after play on Saturday after bowlers Jasprit Bumrah and Mohammed Siraj complained of hearing racist slurs while fielding near the boundary rope.
On Sunday, Siraj approached the umpire pointing towards the stands and the action was paused as police ejected six fans from the ground.
CA launched a parallel investigation with New South Wales Police, promising to take the 'strongest measures' against anyone found guilty of vilification.
"It is most regrettable that an otherwise excellent test match contested in tremendous spirit by two friendly rivals has been tarnished by the actions of a small number of spectators over the past two days," Head of Integrity and Security Sean Carroll said in a statement.
"As hosts, we once again apologise to the Indian team."
Venues New South Wales, which operates the stadium, said CCTV footage was being reviewed to assist the investigation and any fans identified as engaging in racial abuse would be banned from the SCG and other major stadiums in Sydney.
India's Ravichandran Ashwin said the team had been insulted by Sydney spectators in the past but the racial abuse had crossed a line during the ongoing match, which is being played in front of a reduced crowd of less than 10,000.
"It is definitely not acceptable in this day and age. This must definitely be dealt with iron-fist and we must make sure it doesn't happen again," the bowler said.
India's regular captain Virat Kohli was fined half of his match fee in 2012 for responding to barracking from the SCG crowd by gesturing at them with his middle finger.
Kohli, who returned home after playing in the first test to attend the birth of his first child, said racial abuse was completely unacceptable.
"Having gone through many incidents of really pathetic things said on the boundary lines, this is the absolute peak of rowdy behaviour," Kohli said on Twitter. "It's sad to see this happen on the field."
"The incident needs to be looked at with absolute urgency and seriousness and strict action against the offenders should set things straight for once."
Australia coach Justin Langer joined the condemnation.
"It's upsetting and it's disappointing," he said. "It's one of my greatest pet hates in life that people think they can come to a sporting event and abuse or say whatever they like."
"I hated it as a player and I hate it as a coach. It's really sad to see it happen in Australia."
The International Cricket Council said the Indian team had informed match referee David Boon of the alleged racial abuse, on Saturday, and the governing body was 'incredibly disappointed' with the incidents at the SCG.
Under the ICC's anti-discrimination policy, it falls to CA to investigate the incident and submit a report to the Dubai-headquartered body within two weeks.
"We will provide Cricket Australia and the relevant authorities with our full support in any ensuing investigation as we will not tolerate any racism in our sport," ICC Chief Executive Manu Sawhney said in a statement.
A man was banned from attending cricket matches in New Zealand for two years after being found guilty of abusing England fast bowler Jofra Archer during a 2019 tour.