Cardiff Police said they issued 12 fines and 15 other warnings during their first day of car checks to ensure people from outside Wales did not travel to the Welsh capital.
Officers arrested 110 drivers in the first 24 hours of the random check program, which was introduced to stem the spread of the coronavirus.
Twelve fixed penalty notices have been distributed and another 15 people have been given a warning – in which they have been instructed to leave Cardiff – according to police.
People from high risk areas outside Wales are currently banned from entering the country under new Welsh government rules.
Police were given the power to arrest and amend drivers from 9 a.m. on Friday. The move is believed to be specifically aimed at ensuring that people coming from England do not cross the border.
Those who broke the law included a couple from Essex who told officers they were traveling to Cardiff to give Christmas presents to the family, and a group of nine traveling in convoy to visit some friends at university.
Police have been given temporary additional powers following widespread concerns that groups of people from locked areas of the UK, where pubs and bars are closed, were among the crowds that gathered on the streets of central Cardiff last weekend.
Cardiff and Vale of Glamorgan Chief Superintendent Wendy Gunney told reporters yesterday she “would like to thank the vast majority of people who are enjoying their weekends cautiously and within the limits of the regulations in force”, but warned that those who “don’t play by the rules” put their own lives and the lives of others at risk.
“The measures are in place for a reason,” she said, before adding: “Our checks will continue throughout the weekend, and anyone who blatantly breaks the rules, which have been very clear. , is liable to a fine. ”
SI Gunney has confirmed that in addition to vehicle checks, South Wales Police have had more officers on duty and that these changes will be in place until 5 p.m. Sunday – covering the last weekend of England lockdown.
It comes as Mark Drakeford, the Premier of Wales, confirmed yesterday that restaurants and bars will be subject to tighter Covid restrictions in the run-up to Christmas.
The new restrictions, which have yet to be finalized, will take effect from 4 December and are expected to be based on the system in parts of Scotland where no alcohol can be served.
Cinemas, bowling alleys and indoor entertainment venues will also be closed before the festive break. Mr Drakeford said action was needed as the case rate continued to rise as Christmas approached.
The R rate in Wales is currently around 1.4 but it needs to be below one for the number of cases to drop.