THOUSAND OAKS, Calif. (AP) — Authorities say a mountain lion that died last month in the wilderness west of Los Angeles had rat poison in its system.

The lion dubbed P-47 had no visible wounds when it was found dead March 21.

The Santa Monica Mountains National Recreation Area said Tuesday that P-47 had six compounds of a rodenticide in its system. It’s unclear if that caused the death.

Researchers say P-47 may have eaten a squirrel or other animal that ingested the poison, or ate tainted prey.

The National Park Service has found poison compounds in more than a dozen local cougars.