ZCZC FA25
300033 UTC APR
FINNISH NAV WARN 234/26
GULF OF FINLAND.
TSS OFF PORKKALA LIGHTHOUSE:
UNDERWATER SURVEY OPERATION IN PROGRESS
BY SEILI  CALL SIGN OIRO IN VICINITY
OF PSN 59-47.4N 024-25.2E.
SAFETY ZONE OF 0.7*NAUTICAL *ILES**EQUE*TED.
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