Celtic boss Neil Lennon has praised fellow Glasgow club Rangers for their "swift action", following an incident between his captain Scott Brown and one of the rival club's supporters.
A Gers fan was abusing Brown after the Old Firm Derby at Ibrox earlier this month and made a comment about his sister, who died from cancer in 2008.
Rangers have since handed out a lifetime ban to the 15-year-old perpetrator who has also been charged by police.
Forty-eight-year-old Lennon said, "when we're out trying to live our lives, they have no right to abuse or insult people like that.
"I applaud Rangers for the swift action they took and the support a lot of their fans have given to Scott, but it's got to stop. There's no call for that. I've had a brief chat with him about it and I think he handled the situation very well."
Neil Lennon was forced to quit social media during his time as Celtic boss due to the abuse he has received. He said, "it could be quite upsetting.
"It sometimes makes young ones think that it's all right. It's not. We have people in authority and players of the highest calibre asking social media networks to clamp down on it. It has to stop.
"There's no accountability or responsibility for these individuals to stop putting out on a public forum what they want to say. We live in a democracy, but a line has to be drawn somewhere as it is against the law."
Speaking after the incident earlier this month, Brown said, "abuse has happened over the last twelve years of my career. It's hard but it's there, it's sad. It shouldn't be happening.
"I play football, I play to win. Ninety minutes you can shout, you can swear at me as much as you want on the park but don't go into detail like that off the park.
"People can just shout and say what they want and think it's appropriate, it's always difficult not to react."