Police, troops and Interior Ministry officials joined forces to raid two pubs near a university in Chiang Mai for allowing underage patrons to enter.
The first raid was carried out at 11.30pm at the Pen Tor pub, located some 300 metres away from the Maejo University in Chiang Mai's Sansai district.
The authorities found 45 customers under the legal drinking age of 20.
The authorities the moved on to the Safe House pub nearby and found four patrons under 20.
The managers of the two pubs were arrested and charged with selling alcoholic drinks to underage people.
The officials will ask the provincial administration to close the two pubs for five years, as they have both faced similar charges on several previous occasions.
The Pen Tor manger has been identified as Naruemit Rodphra and Safe House manager as Janyawan Muangmala.