A number of students at the school attended by murdered Lucy McHugh have gone to police this week with information, according to their headteacher.

Jason Ashley said it was a “good and very positive” development in the investigation into the 13-year-old's death.

As pupils returned to Redbridge community school in Southampton on Tuesday, Ashley appealed during an assembly for people to come forward with information, assuring them that they would not land themselves in trouble. Since then some students had spoken to police, he said.

Ashley said: “The information is not coming to us as a school, we're just trying to build the bridge to the police – and from what I understand some students have gone forward to the police.

“I will still appeal to anybody in the wider community – the school community – that if they are worried or concerned that they might get into trouble because they know something, the police have given me the authority to say they will not be in any sort of trouble. Everything we're doing in the school is actually trying to do the right thing by Lucy.”

The schoolgirl was found stabbed to death in woodland on 26 July. Stephen Nicholson, 24, was arrested on suspicion of her murder. Last week he was jailed for 14 months over his refusal to hand over the password to his Facebook account.

Nicholson remains on bail for his arrest on suspicion of murder and sexual activity with a child. A charging decision is anticipated on 27 October.