STOCKHOLM (Reuters) - Sweden has protested to Russia after two warships entered its territorial waters without permission, a defence department spokesman said on Wednesday, as Sweden agreed with two neighbouring countries to deepen military cooperation.
The spokesman said Sweden had called in Russian diplomatic representatives to protest the breach on Sept. 14 by "two Russian corvettes which entered territorial waters near Gothenburg".
The Swedish military has also reported that a Danish military vessel entered Sweden's territorial waters without permission on Sept. 16.
Tensions have risen in the Baltic Sea region in recent years, with increased Russian military activity forcing Sweden into a hasty programme of rearmament, including the purchase of Patriot missiles from the United States.
On Wednesday, Sweden, Finland and Norway signed an agreement to deepen military cooperation.
"This is naturally linked to the security situation, which has changed over time," Swedish Defence Minister Peter Hultqvist told Swedish broadcaster TV4.
"We see increased Russian strength in the Murmansk region in terms of marine and other resources, we can see the establishment of a base near Finland's borders ... we see increased strength in the whole of the Arctic region from the Russian side."
Earlier on Wednesday, a Russian navy vessel collided with a Swiss-owned container ship near the Oresund Bridge that links Denmark and Sweden. Authorities in Denmark said the Russian vessel had permission to be in Danish waters and had notified them of its presence.