Finnish seismologists detected five explosions in Russian waters

HELSINKI, (Reuters) – Finnish seismologists detected five underwater explosions in Russian waters of the Baltic Sea last week, the Institute of Seismology at the University of Helsinki said on Tuesday.

“We detected five explosions, the largest of which was 1.8 and the smallest 1.3,” institute director Timo Tiira told Reuters, referring to the Richter scale used to describe the intensity of seismic activity.

Four explosions were reported on Thursday and one on Friday in Russian territorial waters in the Gulf of Finland, Tiira said, adding that it was clear the observations were caused by the explosions and not other seismic activity.

“It can be seen in the shape of the signal and its frequency content,” he said.

The institute did not know what caused the explosions, but that similar disturbances had been detected during previous naval exercises and when cleaning old mines from the seabed, Tiira said.

“We have detected explosions in that same area before, but not very often, not even every year,” he said.

Russia’s Defense Ministry was unavailable for comment.

Reporting by Anne Kauranen; Editing by Mike Harrison

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