People wielding clubs and machetes hunted down the animals in Indonesia.
Images from the scene show a huge pile of bloodied dead crocodiles surrounded by onlookers.
The 48-year-old man was killed after he entered an enclosure at a breeding farm in Papua province while looking for grass to feed his livestock, police and conservation officials said.
The slaughter happened on Saturday, shortly after the funeral of the man.
“One of the crocodile farm employees… heard someone screaming for help and ran to the scene where they saw a person being mauled by a crocodile,” said Basar Manullang, head of Indonesia’s natural resources conservation agency in West Papua.
The man’s family was joined by reportedly hundreds of other locals who marched to the police station to complain about the farm being in a residential area.
They were told the breeder would pay compensation.
Unsatisfied with this response, the mob, armed with clubs, knives, machetes and shovels, went to the crocodile farm and killed 292 crocodiles.
Outnumbered police and conservation officials said they were unable to stop the mob and may pursue criminal charges against those involved, authorities said.
“For now we are still questioning the witnesses,” said district police chief Dewa Made Sidan Sutrahna.
The Southeast Asian archipelago is home to a vast array of wildlife, including several species of crocodile that regularly attack and kill humans.