Swedish military prepared to use 'armed force' as search for 'Russian submarine' continues

Rear Admiral Anders Grenstad, deputy chief of joint operations, said: 'We hate the fact that we have something in our waters'

The Swedish minesweeper HMS Kullen, left, and a guard boat in Namdo Bay, Sweden, search for a suspected Russian submarine (AP)

Sweden would be willing to use force against a foreign submarine believed to have entered the Stockholm archipelago, a senior military official has reportedly said.

Some ships were withdrawn from the hunt today, but Swedish officials stressed that the biggest anti-submarine search operation since the end of the Cold War would continue on land, sea and air.

There was growing anger in Sweden after the military admitted the submarine – suspected to be a Russian vessel – was not the first to have been detected over recent years. The previous cases were not made public.

Rear Admiral Anders Grenstad, deputy chief of joint operations, told BBC News: “If we find the submarine the captain of the ship has the possibility to use weapons to get it to stop whatever it is doing.

“We hate the fact that we have something in our waters – or we believe something is in our waters.”

He added that he did not know which country owned the submarine, saying: “Everybody is speculating .”

Swedish corvette HMS Stockholm patrols Jungfrufjarden in the Stockholm archipelago (AP)

Russian defence ministry officials have denied claims that a Russian submarine got into difficulty in the waters off Sweden and issued a distress signal.

The military spokesman Erik Lagersten confirmed some naval assets, including the corvette HMS Visby, had returned to a base for “maintenance”. He added that the search had now entered “a partially new phase” but denied suggestions the search was being scaled back.

The Swedish military launched the hunt on Friday after receiving what it described as credible reports of foreign underwater activity in waters between the islands that extend from Stockholm, into the Baltic Sea.

The search operation does not appear to have led the submarine to leave with Admiral Grenstad saying on Tuesday there had been more evidence of suspected “foreign underwater activity” near Stockholm. “I can report that there have been two further observations which were made by members of the public that are interesting enough to require follow-up work,” he said.

The uproar over the presence of a foreign vessel in Swedish waters prompted the admission from the military that several such incidents had happened in the last few years. That prompted anger from some who said the public should have been told.

Johanne Hildebrandt, a fellow at the Royal Swedish Academy of War Sciences, told Swedish newspaper The Local: “If this is actually a fact, then the armed forces must have reported it to the politicians, who should have told us. Why haven’t we been informed? And most importantly, why have there been so many cuts to the defence budget if Swedish territory is being violated on multiple occasions?”

Swedish Prime Minister Stefan Lofven yesterday said the country will increase spending on defence as he conceded the military "needs to improve its capacity".

Sweden phased out its anti-submarine helicopters in 2008 and is not expecting replacements until 2018. It has shifted its focus from territorial defence to international peacekeeping operations and abolished conscription.

In 2012 Sweden had 20,000 troops on active duty and 200,000 reserves, down from 50,000 active-duty personnel and almost 600,000 reserves in 1999, according to statistics from the UK-based International Institute for Strategic Studies.

Russian media has claimed Sweden is overreacting. The Nezavisimaya Gazeta newspaper suggested the submarine hunt could be a ploy staged by the Swedish military to boost its defence budget, which has undergone a series of cuts since the Cold War.

The official government newspaper Rossiiskaya Gazeta questioned whether there was any submarine at all, noting nothing had been found by Sweden.

"Either Sweden's echo location equipment is working badly or, as the old saying goes, the eyes of fear see danger everywhere," the paper said.

A defence ministry official quoted by the Tass news agency pointed fingers at a Dutch submarine that participated in an exercise with the Swedish navy last week.

A Swedish armed forces spokesman has said the Dutch submarine was not what triggered the search, while the Dutch navy said the submarine left Sweden on Thursday.

Additional reporting by Press Association