BROOKLYN - Subway riders are often in the dark about service changes while the city's transit agency wastes millions, according to a report.

A report released Sunday by the New York State Comptroller Thomas DiNapoli and New York City Comptroller John Liu says the agency that runs the subways should do a better job of managingdisruptions and keeping straphangers informed.

The report found the agency reroutes trains even when rails receive no work and does not efficiently use repair time. There were also not enough street-level signs notifying riders of service changes.

The MTA says the agency keeps customers updated with website, e-mail and text alerts.