The Hampshire Constabulary drive, dubbed Op Tramline, got underway on the M27 and was led by officers armed with cameras.
The force’s joint operations roads unit, which is linked with Thames Valley Police, said on Twitter: ‘First day of Op Tramline and in the first 3 hours we have evidenced 21 distracted drivers on the M27.
‘People texting, watching TV or driving with dogs on their laps.
‘All caught on camera. #HantsCVU.’
It follows the unit’s drink-driving crackdown over the Christmas period.