Canadian immigration authorities are re-examining citizenship-by-descent applications, prompting some recently approved citizens to return their certificates. Concerns over documentation and proof of lineage have led to renewed scrutiny, though applicants can submit additional evidence to support their claims.

OTTAWA - Some people who received proof of Canadian citizenship under the "Lost Canadians" legislation are now being told to surrender their certificates of citizenship.

Canadian immigration authorities are re-examining citizenship-by-descent applications, prompting some recently approved citizens to return their certificates. Concerns over…