Media playback is unsupported on your device Media caption The Home Office 'go home' campaign is being investigated by the ASA

A scheme which saw vans drive through London calling on illegal immigrants to leave is to be investigated by the advertising watchdog.

The Advertising Standards Authority (ASA) said it had started the inquiry into the Home Office's "go home or face arrest" vans following 60 complaints.

The pilot scheme has faced criticism from the Liberal Democrats and Liberty.

A Home Office spokesman said it was in contact with the ASA and would "respond in due course".

The ASA said it had been "flooded" with calls in support of the scheme following its decision to investigate.

Communities Secretary Eric Pickles told BBC Radio 5 live that the scheme would be rolled out nationally, "if proved effective".

He said: "Given Labour's open-door immigration policy, I don't see anything offensive as suggesting to illegal immigrants that their stay in this country might be shorter than they thought."

'Misleading' claims

The Home Office has said the pilot worked, but did not say how many people had left the country.

Vans were driven around Barnet, Hounslow, Barking and Dagenham, Ealing, Brent and Redbridge as part of the campaign, which started on 22 July and lasted a week.

In a statement, the ASA said the complainants - "individual members of the public" - had expressed concerns that the advert, in particular the phrase "go home", was offensive and irresponsible.

Image caption Conservative MP Peter Bone said the government should be congratulated for the pilot

It said complainants were concerned this was "reminiscent of slogans used by racist groups to attack immigrants in the past and could incite or exacerbate racial hatred and tensions in multicultural communities".

"Separately, some complainants have challenged whether the claim '106 arrests last week in your area' is misleading," the ASA added.

"They've also challenged whether it is misleading because it implies arrest is the automatic consequence of remaining in the UK without permission."

It added that one of the complainants was a former member of the ASA Council, Labour peer Lord Lipsey.

'National Front-style slogans'

A Home Office spokesman said the 106 arrests referred to in the campaign were made across the six pilot boroughs between 30 June and 6 July.

Labour's shadow immigration minister Chris Bryant said: "You've got to question the government's competence. We need effective action on immigration not offensive stunts."

Image caption Liberty, which has criticised the banner, has created its own advert in response

Rachel Robinson, policy officer at human rights campaign group Liberty, said: "Driving National Front-style slogans around ethnically-diverse areas was bound to cause deep offence."

Liberal Democrat business secretary Vince Cable has described the scheme as "stupid and offensive" and Brent Council leader Muhammed Butt said the project was "an act of desperation".

Speaking on Radio 4, Lord Ouseley, a crossbench peer who is the former chief executive of the Commission for Racial Equality, said the advert was contributing to an "element of racism and xenophobia".

But Conservative MP for Wellingborough Peter Bone said the government should be congratulated for the pilot.

"If this works and people voluntarily go home because of it who would have been afraid to come forward before, then it's a good thing," he said.