Youths are being ordered to present themselves for paramilitary-style attacks in Londonderry after getting involved in disputes with loyalists, the police have said.
The police have voiced concern about "worrying signs" of increased paramilitary activity in the city, after a number of young men were seriously injured in beatings.
Superintendent Johnny McCarroll has appealed to community leaders to help put an end to such attacks.
"Two male youths, aged 19 and 20, are at present in Altnagelvin Hospital who have received another severe beating.
"At this moment in time, no complaint has been made by them. I would ask these people to come and make complaints to us."
He described the attacks as "pure thuggery".
"It's pure criminality, it's jungle tactics that's being used. This is horrendous."
The police have said they are going to increase patrols in the Waterside area of the city.
They have appealed to community leaders to help restore calm in the area.