Jason Dingli, 18 of Qormi and a 16-year-old boy from Floriana, have been remanded in custody after being accused in court of seriously injuring a young man and slightly injuring another at City Gate, Valletta, on Friday evening.
They were also accused of taking part in a group of more than 10 with the intent of committing a crime at somebody else's instigation.
The boy, who cannot be named because he is a minor, was also accused of breaking the conditions of several previous court sentences.
Both pleaded not guilty.
The police said that a police sergeant had to be treated in hospital after the accused assaulted him as he was escorting them. His injuries were described as slight, unless there are complications.