Logs player locations every 30 seconds to pos/.log. This is flushed every 5 minutes along with the server autosave. Using a tool like distancecalculator you can then see which players were closest to a suspect area.
Epoch Time Username X Y Z Dimension
1610823328156 ZENITHSEEKER -299.46600535522003 70.0 176.48146299972325 minecraft:overworld
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