Britain sent messages to nearly 60,000 illegal immigrants warning them to leave the country, but the campaign sparked a controversy after some legal migrants, including an Indian-origin rights activist, received the alert.
The Home Office today claims only 14 out of a total of 58,800 people contacted via text, email and post were mistakenly asked if they had overstayed their visas, but campaigners believe the true number is far higher.
Indian-origin human rights and anti-racism campaigner Suresh Grover expressed shock after he received the message.
"I was absolutely shocked and quite horrified to receive the text. I thought it wasn't meant for me," he said.
"I came here with my parents in 1966, I was born in East Africa and have always had a British passport," said Grover, who is now consulting his lawyers on the matter.
The controversy gained further ground after Prime Minister David Cameron's office was asked to justify the campaign.
"The prime minister agrees with the principle of the texts. It is one of various means the Home Office contacts people who may not have the right to remain in the UK," the PM's official spokesperson said.
He acknowledged that the wording of the texts had changed since the campaign began. Originally, they included the phrase: "You are required to leave the UK as you no longer have the right to remain."
The messages now read: "Our records show you may not have leave to remain in the UK. Please contact us to discuss your case."
The messages were sent by private contractor Capita on behalf of the UK Border Agency (UKBA), which received 140 complaints.
"Most complaints occurred in the early part of the contract where Capita was, as part of the contract, updating sometimes out-of-date Home Office records," Capita claimed.
The Opposition Labour party described the Conservative-led government's tactic as "shambolic and incompetent".
