The deadline for completing Scotland’s census has been extended until the end of May because of low completion rates.

Just under a quarter of households have still to send a response to the survey.

The Scottish government said it would keep it open for an extra four weeks, until 31 May.

Scotland’s constitution secretary, Angus Robertson, told Holyrood it was important for the government to hear the voices of the households still to return their surveys.

Census letters were sent to 2.7 million homes, representing 5.5 million people.

Two million households have filled in their survey responses, equating to 77.2%, but an estimated 604,000 had still to submit them last week.