ZCZC FA18 311311 UTC AUG ESTONIAN NAV WARN 142/26 GULF OF FINLAND. 030500 - 031400 UTC SEP NE OF OSMUSSAAR ISLAND FIRING PRACTICE AREA 1A CENTRED 59-22N 023-33E FIRING EXERCISES IN PROGRESS. OTHER VESSELS MUST AVOID ENTRY INTO THE AREA. STANDING BY VHF CH 16 AND 61. CANCEL 031400 UTC SEP. NNNN