The Home Office has issued its second apology over a data protection blunder in less than a week.
In the latest error, 240 email addresses were mistakenly shared in responses to enquiries about the settlement scheme for EU nationals seeking to remain in the UK after Brexit.
This came days after it emerged that the department made a similar mistake in emails about its Windrush compensation scheme.
An independent review has been commissioned to examine the Home Office's compliance with data protection obligations, while "strict controls" have been placed on the use of bulk emails for communicating with the public.
Immigration Minister Caroline Nokes gave details of the latest incident in a written statement to the House of Commons on Thursday.
Noting that the Home Office receives a large number of enquiries in relation to the EU settlement scheme, she said: "When responding to generic enquiries, responses are sent in batches.
"The process for this is such that recipients would not normally be able to see the other email addresses.
"Regrettably, it has come to my attention that on Sunday 7 April three emails were sent that did not follow the appropriate procedure and 240 email addresses were made visible to other recipients.
"No other personal data was included in the communication. We have written to all individuals who received this email to apologise."
On Monday, Ms Nokes disclosed that an "administrative error" meant that emails sent to some individuals and organisations who had registered an interest in being kept informed about the launch of the Windrush compensation scheme included email addresses of other recipients.
Five batches of emails, each with 100 recipients, were affected.
In her statement on the second case, Ms Nokes said "strict controls" have been placed on the use of bulk emails when communicating with members of the public "to ensure this does not happen again as lessons are learned".
She added: "An independent review of the department's compliance with its data protection obligations has also been commissioned."
The EU settlement scheme allows European nationals and their family members to apply to secure their right to stay in the UK after Brexit.
It has received more than 400,000 applications so far.
Ms Nokes insisted the scheme is "performing well", but Liberal Democrat Home Affairs spokesman Sir Ed Davey said: "We've already heard far too many cases of EU citizens facing technical problems or being wrongly refused.
"Now 240 have had their privacy compromised.
"And it will only get worse if Brexit goes ahead. On this evidence, we are heading straight for another Windrush scandal."