Harris County has cancelled nearly 8,000 voter registrations this year for a reason the state lists simply as "investigation," about three times as many as during the same months last year, according to an ABC13 analysis of state records.

County and state election officials say the increase reflects routine voter-roll maintenance that Harris County had to put off while it ran back-to-back elections, then caught up on after the March primary.

Every month, the Texas Secretary of State publishes a report showing how many voter registrations each of the state's 254 counties cancelled, and why.