STOCKHOLM (AFP) - A Swedish peace group said Tuesday it has lowered a sonar device into the Baltic Sea off Stockholm to deter Russian submarines, emitting the message "This Way if You Are Gay".

The Swedish Peace and Arbitration Society's (SPAS) cheeky device emits the message in Morse code and is designed to scare off subs from Russia, which does not share Sweden's acceptance of homosexuality.

The so-called Singing Sailor also features a flashing pink neon outline of a seaman clad only in white underpants and a boater's hat, gyrating his hips above the text "Welcome to Sweden - Gay Since 1944."

That was the year when Sweden decriminalised homosexuality. In contrast, rights groups have recently sounded the alarm over a rising number of homophobic attacks in Russia, saying that a ban on "gay propaganda" effectively legalises discrimination.

SPAS said on its website that its device was made to provide "interesting info for any submarines passing close by".

In October last year, Sweden's navy launched a massive hunt for a foreign submarine, suspected to be Russian, in the Stockholm archipelago.

The military subsequently confirmed that "a mini submarine" had violated its territorial waters, but was never able to establish the vessel's nationality.

Following the incident, as well as several airspace violations by Russian jets over the last year, the Swedish government announced in April that it would raise defence spending by 10.2 billion kronor (S$1.65 billion) for the period 2016 to 2020, largely due to concerns over Russia's military resurgence.

SPAS said its campaign was aimed at urging the Swedish government "to think in new ways instead of falling back on territorial defence, conscription and rearmament - the world doesn't need more weapons".

"Military rearmament in itself is a major contributing cause of conflict," it added.