Mario P., as he is called according to the daily Le Parisien, was being held in custody in the village of Bessé-sur-Braye, 55 km from Le Mans on Wednesday.
Mario P. was taken in for questioning after the body of 55-year-old neighbour Philippe Emery was discovered on Tuesday upside-down in a bin full of water.
Emery’s head had been smashed and it is suspected he might have drowned.
Mario P. is suspected of killing the victim over an incident early February involving dead goldfish. Mario had lent the victim his goldfish while he was away. But the victim left Mario’s aquarium on his doorstep, where the fish died in the cold.
Since this incident, Mario P. and his neighbour had stopped speaking to one another. Mario P. was also seen washing his courtyard – which he shared with the victim – with bleach and plenty of water.