NEW YORK (AP) — The failure of security cameras in the New York subway station where a gunman opened fire this month is being investigated.

The Metropolitan Transportation Authority’s acting inspector general announced the probe Monday. Police acknowledged that security cameras in three stations weren’t working on the morning of April 12, including the station where the alleged gunman set off a smoke bomb and shot 10 people.

“The work will encompass relevant allegations and concerns that are within the scope of the OIG’s jurisdiction as the independent agency statutorily charged with MTA oversight,” Acting MTA Inspector General Elizabeth Keating said. “Consistent with OIG policy, we will not comment further on the review until it is completed and released publicly through our normal process.”

Other cameras in the subway system helped police track suspect Frank James’ movements after the shooting. James also left behind a bag containing weapons, smoke grenades and the key to a U-Haul truck he had driven.

The MTA has nearly 10,000 cameras at its 472 subway stations. The NYPD said reports the lack of cameras “delayed the manhunt” are “unfair and misleading.

“The MTA cameras in other parts of the system were essential elements in determining his movements before and after the shootings,” NYPD Deputy Commissioner John Miller said. “Their personnel worked with us around the clock to identify and retrieve images in this case. While it has become routine to cast blame in many directions after an incident we should remember that the gunman is the sole party responsible for this attack.”

The MTA provides live feeds to the NYPD from 5,100 cameras, according to Miller. Additionally, 5,000 cameras record local across the system.

“We communicate with the MTA about outages when they occur. If we discover an issue with a feed, we report it to them to make sure they are aware,” Miller said.

The MTA Inspector General encourages all members of the public to reach out with complaints, tips, or to report fraud via the Office’s confidential tip reporting portals: Online (https://mtaig.state.ny.us/Pages/ComplaintForm.aspx), Phone 1-800-MTA-IG4U (1-800-682-4448) or Email (Complaints@mtaig.org).