Intriguing news from South Tyneside, with the announcement that three independent councillors on the town council have crossed the floor to join the UK Independence Party (Ukip).

On Friday morning Ukip's deputy leader Paul Nuttall travelled to South Shields to meet his new councillors: George Elsom, Steve Harrison and Linda Hemmer.

The move means Ukip will become the official opposition in the Labour stronghold.

Labour now holds 48 of the 54 council seats on South Tyneside Council. There is one Conservative, Jeff Milburn, in Cleadon and East Boldon, and one independent, Jane Branley, in Westoe.

The news was greeted with weary resignation by Iain Malcolm, Labour leader of the council. "As Harold Wilson once said of Tony Benn, some people immature with age," he said in a phone interview. "This for me is the last desperate throw of the dice for three people who know they will soon face very hostile re-election campaigns."

He added: "Whether these three are so sure of the support of the electorate that they should resign and fight byelections for their new party, I will leave that up to their consciences."

Malcolm said he was most surprised to see Elsom defect to a rightwing party like Ukip. "He's more leftwing than Tony Benn. I've known him for a long time and he has always had a very strong centre-left outlook on life."

In an interview with the Shields Gazette on Friday, Elsom admitted he didn't share all of Ukip's policies and Coun Elsom, who represents Cleadon Park, acknowledged he does not agree with all UKIP policies and admitted there would be an element of "suck it and see" over the switch.

According to Malcolm, all three defectors were once Labour party members.

On 27 June Ukip will try to add two more councillors to their ranks when byelections are held in two South Tyneside wards. A seat in the Primrose ward is up for grabs after the incumbent, Emma Lewell-Buck, won David Miliband's parliamentary seat in a byelection last month. Another is on offer in Cleadon and East Boldon following the death last month of 30-year-old David Potts, who was elected on a Tory ticket but defected to Ukip while in office.

The latest move comes after Ukip came second in the recent South Shields byelection with almost 25% of the vote. According to Richard Elvin, who stood for Ukip against Lewell-Buck, local party ranks have swelled in recent weeks. Ten days ago Ukip officially opened a South Tyneside branch, and now has around 100 members, he said – up from around 30 before the byelection.

Harrison and Hemmer had actually campaigned for Ukip during the byelection, said Elvin, after realising their local policies "were almost identical to ours." Then he said, "it was just a question of dotting the i's and crossing the t's."

Elsom, who represents the Cleadon Park ward, said in a press release: "The Labour Party has been in power in South Tyneside since the borough was created in 1974 and has ruined the centre of South Shields and the rest of the borough.

"An effective and strong opposition is essential to stop the further deterioration. Nationally I agree with most of Ukip's policies especially those on Europe, immigration and energy. By joining Ukip, a national party, I am hoping that the resources on offer will be such that it will help us to defeat the Labour machine."

Hemmer said: "Family, friends and residents support my choice in joining UKIP as like me they feel this will help strengthen the voice of the people. Due to the policies of UKIP the people of our ward will still have faith that I will still only answer to them."

Harrison said: "I very much agree with Ukip's policy to stop open door immigration. UKIP don't operate the "whip" system which means we are free to vote with our conscience for the benefit of our constituents".

Ukip's irrepressible leader, Nigel Farage, also put in his tuppence, saying: "I am delighted to welcome George, Steve and Linda to the party. They have a wealth of experience gained while serving their community as Independent councillors which can only add to the strength of Ukip.

"It's good to know we have taken on three new ambassadors who can help us to help the people of the North-East, as well as the country as a whole."