A former NYPD cop from Centereach who is accused of fatally stabbing his girlfriend before jumping in front of a subway train and losing his legs has filed a notice of claim against the MTA saying that his injuries were a result of falling and negligence by the transit agency.

In the notice of claim — a precursor to a lawsuit — filed Wednesday, ex-cop Arthur Lomando is seeking $50 million in damages.

Prosecutors say Lomando stabbed his girlfriend, Suzanne Bardzell, 48, with a machete-like knife at her New Jersey home on Oct. 22; the special education teacher, who had two teenage sons, died at the scene that afternoon, authorities said.

After stabbing Bardzell, Lomando went to Harlem where, prosecutors say, he jumped in front of a subway train. He was taken to Harlem Hospital Center, where his legs were amputated. He also had severe head injuries.

The notice of claim says his injuries were sustained “through the alleged negligence and tortuous conduct” by the MTA. First, Lomando fell from the platform at the subway station at 168th Street and Broadway during rush hour when it was “overcrowded,” according to the filing. Plus, the platform also “contained slippery substances” and he was “struck by falling debris on the platform which caused him to fall, and/or trip,” the filing says.

Also, the notice of claim says “as the claimant lay on the tracks ... the train operator, in the exercise of reasonable care ... should have been able to observe the claimant and stopped the train before” striking him.

A spokeswoman for the Metropolitan Transportation Authority said Friday the agency did not comment on pending litigation.

In 2004, Lomando was fired after 10 years as an NYPD officer, days before his disability retirement was to take effect, court records show.