Image caption Bill Newton-Dunn is critical of UKIP

Britain's longest serving MEP, who lost his seat in last week's European elections, has launched a stinging attack on UKIP.

Liberal Democrat Bill Newton-Dunn, who represented the East Midlands region, was first elected to the European Parliament in 1979.

The Lincoln-based politician was a casualty of the collapse in the Liberal Democrat vote across the UK - which left the party with just one MEP.

Mr Newton-Dunn said: "UKIP were full of lies and exaggerations and were just scaring people. They are like the Luddites of 2014."

The former MEP said UKIP should not take their seats in the European Parliament.

He suggested Nigel Farage's party should follow the lead of Sinn Fein, whose MPs have traditionally declined to sit in the House of Commons.

Mr Newton-Dunn said: "Will UKIP MEPs take the salaries and expenses but do nothing while they are there for five years except rack up a huge cost to British taxpayers?"

Newly-elected UKIP MEPs have hit back at the suggestion they should not take their seats in the European Parliament.

Eyes and ears in Brussels

Yorkshire and the Humber MEP Jane Collins said: "People voted for UKIP because we are their eyes and ears in Brussels.

"We are there to expose the legislation, the directives and to expose the establishment which is undemocratic and out of control."

UKIP topped the poll in Yorkshire and the Humber and the party trebled its number of MEPs in the region from one to three.

In the East Midlands region - which covers Lincolnshire - UKIP also polled the most votes and secured two MEPs.

Nigel Farage has named Great Grimsby and Boston & Skegness as two of the constituencies UKIP is targeting at the general election.

Great Grimsby is currently held by Labour's Austin Mitchell, who is stepping down in 2015.

Mr Mitchell said the first past the post voting system would make it difficult for UKIP to win seats in a Westminster election.

The European elections saw UKIP poll more than 50% of the vote in Boston.

However, the Conservative MP for Boston & Skegness, Mark Simmonds, said he was confident he would be re-elected at the general election.