Prosecutors "must take a hard line" in any case of online hate comments about the Glasgow helicopter crash, the Lord Advocate has said.

Police are investigating comments made about the tragedy which killed nine people when a police helicopter crashed into the Clutha bar on November 29.

A 16-year-old boy was arrested last week for allegedly posting sectarian and racist comments online about the incident.

Lord Advocate Frank Mulholland wants a "robust prosecution policy" and guidance is to be issued to prosecutors this week on how they should deal with hate crimes linked to the Clutha helicopter tragedy.

Procurators fiscal will be told that where it can be demonstrated that such an offence was motivated by a reaction to the events at the Clutha bar there will be a presumption in favour of criminal proceedings and all such cases must be reported for Crown Counsel's instructions.

The Lord Advocate said: "It is important that the Crown Office and Procurator Fiscal Service demonstrates a robust prosecution policy towards such offences committed as a reaction to the incident in recognition of the fact that people died and the impact such crimes will have on their families and friends.

"This is also in consideration of the other people who were in the Clutha bar and those who attended the scene in the aftermath.

"I have made it clear that prosecutors must take a hard line against this kind of hate crime."

The first of the funerals for the victims of the crash took place yesterday with a service for helicopter pilot captain David Traill at the University of Glasgow.

Prayers were said at the service for the eight others who died in the crash.

Police Constables Kirsty Nelis, 36, and Tony Collins, 43, were on board the helicopter and the six who died inside the pub were Robert Jenkins, 61, Mark O'Prey, 44, Colin Gibson, 33, John McGarrigle, 57, Gary Arthur, 48, and Samuel McGhee, 56.