Police are probing an attack by youths hurling bottles on a group taking part in a tour of Londonderry.
Although the incident happened on Saturday, details only emerged today.
Police said they are treating the incident as homophobic due to the nature of the abuse being shouted.
The tour party were on Rossville Street on Saturday when youths began to throw bottles and verbally abuse them.
The tour party were in Derry to visit the Rainbow Project, a support group for gay people, and as part of the visit were taking a tour of the city.
Police at Strand Road are appealing for information regarding the attack. One of the thugs who attacked the tour party was described as wearing a black and green woolly hat, black jacket and navy tracksuit bottoms.
Sean Morrin, of the Rainbow Project, said: "We had a party of 17 from outside Derry - from across the North and one person from Australia - visiting the Rainbow Project.
"As part of the visit we took them on a tour of the Walls and when we were in the Bogside a couple of very drunk youths were pointing pellet guns at the party. They then threw the beer bottles they had been drinking from. The party got out of there very quickly.
"This sort of behaviour is a blight on the city, but the tour party knew this wasn't what the city is like. They all said they would return again."
Mickey Cooper of Free Derry Tours, who had a tour in the area at the time, said: "I had a tour party in the area when it happened around 2.30pm. I heard some glass breaking and saw a couple of tourists crossing the street, quickening up their pace, but they weren't with my tour party.
"The tourists I saw were standing by the (Operation) Motorman mural when the bottles were thrown. There is a hardcore of seven or eight youths causing the trouble and they are putting off groups of tourists coming to Derry.
"This is the sort of thing we definitely want stamped out. It is totally counter-productive to the image of the city we are trying to portray. These people are not representative of the youths in the Bogside.
"If anybody knows their names or who they are, they should tell us at Free Derry Tours or another relevant body so we can work towards stamping out this sort of behaviour."
A police spokesperson said: "This was a totally unwarranted attack on a group of people out to enjoy the sights of the city. The behaviour of these youths is unacceptable and incidents like this reflect badly on the reputation of the city.
"We would appeal to anyone who was in the area and could help identify the culprits to come forward. The number to call with any information is 0845 600 8000 or Crimestoppers on 0800 555 111."