He appealed for the killer or killers to give themselves up and called for witnesses to come forward. He added that there was no evidence of any theft and would not be drawn on the motive for the murder. Asked about suggestions that a sub-continent betting mafia had been involved, Shields said: "Everything you have heard would be a line of inquiry."
Please explain the highlighted group of words.
1 Would not speculate on or discuss the motive
2 Sub-continent = South Asia - the Indian sub-continent mafia = organies crime
3 The suggestions that have been made, like the betting mafia, are things the police are investigating