WASHINGTON (AP) — Metro is spending millions of dollars to triple the number of video cameras it has monitoring its stations and parking garages, and to put cameras in rail cars for the first time.

The agency plans to increase the number of cameras it uses to watch for crime and security threats from 1,900 to nearly 6,000, it said in documents provided to the D.C. Council. That will cost $6.5 million, an agency spokesman said.

Metro previously announced plans to spend $7.1 million to install cameras in six rail cars by the end of 2013, as well as build a network to allow officials and police to watch those cameras in real time.

“As the second-busiest subway system in the U.S., serving the nation’s capital, there should be no question about Metro’s potential to be a target. We have no greater responsibility than protecting the safety of our customers, visitors and employees,” Metro spokesman Philip Stewart said in an email. “To that end, we are in the process of deploying a comprehensive next-generation security system for Metro.”

The agency often pays for security upgrades with federal grants, but federal funds are paying for only “a portion” of the thousands of new cameras, Stewart said.

The cameras will help operators in Metro’s control centers have a better idea of what’s going on at stations and parking garages, Stewart said. That could help the agency avoid crowded platforms and other safety hazards.

The new cameras also will have better image quality, Stewart said — “akin to the difference between VCR and Blu-ray.”

Poor image quality was an issue in the January 2011 death of 63-year-old Lou Stancari, whose body was found on the tracks at Farragut North the morning after he paid his fare at Dupont Circle. Camera images were vague and fuzzy and offered few clues into what happened the night of his death, family and friends said. One camera was pointing down at the floor instead of across the station, friends said.

The agency also will have four cameras in each of its new 7000 series rail cars, the first of which are due to arrive next year. Many Metrobuses already have cameras.

Privacy advocates have voiced concern about proliferating cameras, but crime victims have praised Metro’s camera system for helping police find suspects.