A video, shared on social media, which was taken in a play area in West Park, Wolverhampton, appeared to show a group of young men shouting abuse and threatening to stab members of a Muslim family on Saturday.
It also shows two of the group getting physically aggressive, with one of them hitting the phone out of the hands of the person taking the video.
West Midlands Police confirmed on Monday evening that two teenagers, aged 15 and 17, had been arrested on suspicion of racially-aggravated assault.
On Thursday a spokesman for the force confirmed that the two teenagers had now been released pending further investigation.
On Tuesday it was confirmed that windows were smashed and a man was injured in what is believed to have been a revenge attack following the West Park incident. Around 10 men were reported to be smashing windows at a house in the Whitmore Reans area of the city on Monday evening.
Police believe the attack was carried out in retaliation for the incident in West Park on Saturday. A spokesman confirmed that no arrests have been made in connection with the Whitmore Reans incident.
Senior police officers have urged people to stay calm, unite and not take matters into their own hands.
Chief Inspector Hasson Shigdar, of Wolverhampton Police, said on Tuesday: "We know there is a great deal of anger and frustration following an incident in West Park and we understand that.
"But we are asking our communities to now pull together and remain calm as we work to bring those involved to justice.
"We also do not want these incidents to cause any more harm or upset than they already have so we are asking people to no longer share footage as this can only stir up further resentment and anger."