Cameras that failed to capture subway shooting were flagged as faulty days earlier.

A subway safety digital camera system that didn’t seize pictures of a mass taking pictures in a Brooklyn station on Tuesday had been flagged by New York Metropolis Transit employees as malfunctioning two days earlier, transit officers mentioned.

Upkeep employees inspected the digital camera on Sunday and traced the issue to a fiber-optic cable connection failure that had additionally interrupted feeds from cameras in two different stations: the native cease instantly earlier than the scene of the taking pictures and the one instantly after it, the officers mentioned.

The digital camera system failures difficult the seek for the shooter, who wounded 10 folks and brought on accidents to not less than 13 extra when he opened hearth on a crowded N practice on the thirty sixth Avenue station through the morning rush, and disadvantaged investigators of vital data from the scene. The authorities believed, for instance, that the shooter left the N practice on the thirty sixth Avenue station after which crossed the platform to board a neighborhood R practice that took him one cease north. However none of that was captured on video due to the digital camera system downside.

Tim Minton, a spokesman for the Metropolitan Transportation Authority, which oversees the subways, mentioned the digital camera system glitches on the thirty sixth Avenue station traced to “a node in a server room” that failed over the weekend however added that pictures of the suspect had been captured by cameras and expertise elsewhere within the transit system.

“The suspect was capable of be seen, and actions evaluated, with the M.T.A.’s help,” Mr. Minton mentioned.

The malfunctions additionally increase issues in regards to the state of the subway’s safety programs at a time of intense public nervousness stoked by a collection of violent incidents on the town’s transit system.

Particulars of the surveillance system failures emerged because the police introduced the arrest of the suspected gunman, Frank R. James, 62, who was taken into custody on Wednesday in Manhattan’s East Village.

The M.T.A. has within the final a number of years tried to increase its use of surveillance cameras within the New York Metropolis subway system, and final fall introduced that it had positioned them in all 472 stations. In 2005, the system solely had cameras in about half its stations. Nonetheless, there are not any cameras on subway trains and in lots of strategic places.

The cameras that the M.T.A. has now fluctuate in high quality. Some, put in in a rush to verify each station was coated, have much less definition and functionality for real-time monitoring, as others can do, mentioned Andrew Albert, an M.T.A. board member.

“Hopefully we get much more of these,” Mr. Albert mentioned, noting {that a} man arrested on costs of raping a girl in Central Park final yr had been captured on video getting into a close-by subway station.

The M.T.A.’s board final month accredited a $50 million contract to put in closed circuit cameras close to turnstiles and gates in 88 stations, data present. Some officers say monitoring such areas could make subways safer as a result of many who commit crimes within the system achieve this after leaping turnstiles.

“There are millions of cameras on the market, significantly in the important thing hubs,” mentioned Jason Wilcox, who was named the New York Police Division’s transit chief in January, at an M.T.A. transit committee assembly in March. “In terms of cameras, clearly extra is healthier. You already know, it helps us out in so many vital methods.”