Officers were called to the 15-year-old girl's south Edinburgh home by worried neighbours and later seized 17 litres of alcohol from teenage revellers.

The raid took place in the final week of a month-long summer blitz on alcohol abuse and antisocial behaviour among teenagers across the force area. A total of 34 under-18s – 25 boys and nine girls – were detained by police patrols during the operation for drinking in public and their parents were alerted. Nearly 400 litres of alcohol, including beer, cider, alcopops and vodka, were confiscated and poured away in front of the youths.

Alcohol safety campaigners today welcomed the clampdown, which was mounted to coincide with the school summer holidays. They warned that the cheap price of alcohol meant many youngsters could use pocket money to get drunk for the same price as a visit to the cinema.

During the operation, which ran between July 14 and August 10, Lothian police also charged 42 men and 42 women with breaking by-laws which prohibit the drinking of alcohol in public. Public drinking bans are in effect at Hunter Square, Leith's New Kirkgate centre and Muirhouse Shopping Centre, as well as most towns and villages in East, West and Midlothian.

Superintendent Stephen Harvey, from the force's safer communities department, said: "It was the last week of the campaign when we were called to the house in south Edinburgh. The owners were away on holiday but their 15-year-old daughter, who was supposed to be staying with friends, had organised an 'open party'.

"More than 20 under-agers were met by police as they arrived at the party and had their carry-outs seized – which added up to 17 litres worth – and disposed of."

The blitz saw plainclothes and uniformed officers check drinking "hotspots" across the force the area, which included parks and pathways. Temporary and mobile CCTV cameras were used in some areas to track down under-age drinkers.

Test purchases, where police send under-18s into off-licences to try to buy alcohol, resulted in three of the 48 premises failing.

Adults who buy alcohol from youngsters were also targeted. Five were charged and reported to the procurator fiscal.

The operation was carried out as part of Safer Scotland's national anti-violence initiative.

Supt Harvey added: "This has been a successful campaign which was not only aimed at curbing teenage drinking, but also antisocial behaviour and violence which can go along with that."

Jack Law, chief executive of Alcohol Focus Scotland, said: "This crackdown will hopefully have raised awareness among children and their parents that drinking alcohol at such a young age is both illegal and dangerous.

"Booze is being sold at pocket money prices – it's far cheaper to get drunk than to go to the cinema or leisure centre. We need to stop the supply of alcohol by reviewing the licences of shops selling to under-18s and imposing harsher penalties for adults who buy alcohol on their behalf."