Terror attacks carried out by Islamists likely contributed to a huge spike in 'Islamophobic' tweets in July, according to the BBC.
Data showed that across the world, almost 7,000 anti-Islamic tweets were sent in English every day last month.
More than 21,000 were sent on July 15, one day after the Nice attack, during which 85 people were killed when a gunman drove a heavy lorry into crowds celebrating Bastille Day in the French Riviera city.
ISIS subsequently claimed that suspect Mohamed Lahouaiej-Bouhlel, 31, was "one of the soldiers of Islamic State".
Other days that saw a spike in the number of 'Islamophobic' tweets were July 26, when Catholic priest Fr Jaques Hamel was murdered by Islamists in Rouen, and the period following an ISIS attack in Baghdad on July 3.
According to think tank Demos, which analysed the data, these events "were the most likely causes" of the increase in anti-Islamic tweets.
Research director Carl Miller described the posts as "damaging, harmful, and tremendously problematic".
They were examples not of people "being angry at Islamic State, [but] people who are being angry at the wider Muslim world," he told the BBC.
However, only a minority of the tweets sent were illegal.
"Only when there's an actual threat to life are people actually breaking the law, and therefore the people that are in the online space are actually far less protected than the offline space when it comes to receiving that kind of abuse," Miller said.
A spokesperson for Twitter said the site is "continuing to invest heavily in improving our tools and enforcement systems to better allow us to identify and take faster action on abuse".