A 31-year-old man was arrested on Friday after air support were called to an incident at Holbeach St Marks.
Officers from East Midlands Operational Support Service were involved in the arrest, which came after a vehicle ended-up in the river at Pode Hole.
The arrest was part of Operation Galileo which is targeting hare coursers visiting Lincolnshire to commit offences.
Friday also saw the arrest of a 34-year-old man from Camberley, a 40-year-old from Bracknell and a 30-year-old from Wokingham in Long Sutton on suspicion of being in a stolen vehicle. Police recovered a Mercedes and four dogs were seized.
All the men were later released pending further investigation and evidence gathering.
So far the operation has seen a total of 40 dogs and 16 vehicles seized as part of the operation.
A total of 34 people have been arrested or reported for summons.
Lincolnshire police are asking residents to look out for suspicious activity, and if coursing is in progress, use 999.
