Air travellers arriving in Scotland from Tuesday will be subject to quarantine spot checks for the first time, after the country reported four days without deaths from Covid-19. Nicola Sturgeon, the first minister, said her officials and advisers were still deciding which countries would not be subject to quarantine checks, four days after the UK Home Office released its list of 74 “air bridge” countries and territories. Sturgeon said there had been no deaths reported from Scottish hospitals over the preceding 48 hours, bringing the number of days without deaths of confirmed Covid-19 patients to four. She added four new positive cases were reported for Sunday. Sturgeon said her administration was still evaluating the UK government’s overseas coronavirus data given there were hotspots still emerging, including in Spain, a country on the Home Office’s green list of quarantine-free destinations. The Scottish list would be announced before 10 July, the date the UK rules come into force. From Tuesday, all passengers from overseas destinations will be subject to possible spot checks to ensure they self-quarantine for 14 days or face a £480 spot fine or up to £5,000 if the case goes to court. So far, no passengers flying into Scotland have yet been subject to any spot checks despite the introduction of the quarantine rule on 8 June, due to a lack of access for Public Health Scotland officials to Home Office passenger data. That escalated into a row between the Scottish Conservative leader, Jackson Carlaw, and senior Scottish National party MSPs, including Jeane Freeman, the Scottish health secretary, at the weekend over responsibility for the delay. “Sturgeon and her failing ministers are putting us all at increased risk during this pandemic,” he said. Carlaw said Scotland was the only part of the UK not to have done any quarantine checks; in Northern Ireland, England and Wales, air travellers were contacted three times by text and had follow-up calls. Sturgeon said on Monday there were issues with data quality which had to be resolved. “We took the decision to manage this part of the system within our own public health arrangements so there required to be work done to conclude a memorandum of understanding that would allow the data to flow from the Home Office to Public Health Scotland,” she said. She said the Border Force had reported high levels of compliance with the voluntary self-quarantine regime. She confirmed further details about the next stage of easing the lockdown would be released on Thursday, as Scottish pubs and entertainment venues were allowed to open beer gardens on Monday. Some venues have set up beer gardens for the first time, to attract customers. Sturgeon also said a small outbreak in Dumfries and Galloway that included a case in Carlisle which led to a local lockdown being extended last Thursday, was likely to be contained. She said 12 new cases had been detected, but there was no evidence of wider transmission. The lockdown was likely to be relaxed within 24 hours, she said. Sturgeon indicated the Scottish National party could investigate if any of its members were found to be involved in an abusive protest against travellers driving over the English border of the A1 on Saturday. Humza Yousaf, the Scottish justice secretary, described the demonstrators as “horrible, reprehensible and vile” after footage emerged of them shouting “stay the fuck out” and “plague carriers” at caravans and campervans driving north. Sturgeon said: “I can’t stop people waving SNP banners but I can be very clear that they don’t speak for us and we will be ... I’m not going to talk about internal disciplinary arrangements in the SNP [but] we have got well-established disciplinary rules which will be used if necessary. “But I can’t be clearer than I have been: the SNP is an open, welcoming party; Scotland is an open and welcoming country and that protest is not something I condone or endorse in any way, shape or form.” The demonstration follows reports of a similar incident on a bridge over the A30 as it entered Cornwall, where an image on social media purported to show three people standing on a bridge over the A30 holding a sign that read “Turn around and fuck off”.