Norway and Denmark will increase security and surveillance around their energy infrastructure sites after the alleged sabotage of Russia's Nord Stream gas pipeline in the Baltic Sea.
Major leaks struck two underwater natural gas pipelines running from Russia to Germany, with experts reporting that explosions rattled the Baltic Sea beforehand.
Norway -- an oil-rich nation and Europe's biggest supplier of gas -- will strengthen security at its land and offshore installations, the country's energy minister said.
The Scandinavian country's Petroleum Safety Authority also urged vigilance on Monday after unidentified drones were seen flying near Norway's offshore oil and gas platforms.
"The PSA has received a number of warnings/notifications from operator companies on the Norwegian Continental Shelf concerning the observation of unidentified drones/aircraft close to offshore facilities" the agency said in a statement.
"Cases where drones have infringed the safety zone around facilities are now being investigated by the Norwegian police."
Meanwhile Denmark will increase security across its energy sector after the Nord Stream incident, a spokesperson for gas transmission operator Energinet told Upstream.
The Danish Maritime Agency has also imposed an exclusion zone for five nautical miles around the leaks, warning ships of a danger they could lose buoyancy, and stating there is a risk of the escaping gas igniting "above the water and in the air."
Denmark's defence minister said there was no cause for security concerns in the Baltic Sea region.
"Russia has a significant military presence in the Baltic Sea region and we expect them to continue their sabre-rattling," Morten Bodskov said in a statement.
Video taken by a Danish military
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