The House Oversight and Reform Committee obtained documents from an anonymous source at the Census Bureau showing that “unresolved errors may be more extensive than first reported.” The additional errors could hurt President Trump’s plan to exclude undocumented immigrants from population figures that determine House apportionment.

Rep. Carolyn Maloney sent a letter on Wednesday to Commerce Secretary Wilbur Ross, whose agency oversees the Census Bureau, demanding a set of documents about the reported errors the committee requested last month but were never handed over due to “concerns about ongoing litigation.”