' fans believed something was seriously wrong with the singer after her Instagram account disappeared ... calling the cops to her home to see if she was in danger.
Law enforcement sources tell TMZ Britney deleted her Instagram account -- something she's done many times -- at some point within the last 12 hours. For whatever reason, fans became alarmed, believing the deleted account meant Britney was in trouble ... and called the Ventura Co. Sheriff's Office.
Deputies from the sheriff's office then went out to Britney's home and determined there was no reason to believe she was in danger. It's unclear if they spoke to Britney directly, or if someone else assured them she was OK.
The incident comes less than two weeks from when Britney was spotted at a local restaurant where witnesses tell us she became "manic,"
frustrating her husband, Sam Asghari
, to the point of getting up and leaving. Video, obtained by TMZ, showed Spears babbling nonsense at the table.