A woman was struck and killed by a train in Queens early Tuesday morning, leading to significant delays on several transit lines, officials said.

The woman, identified by police as Jessica Marleny Ajtzac Guarcas, 18, was struck at the 74th Street and Roosevelt Avenue station in Jackson Heights around 6:40 a.m, the NYPD said.

Officers who arrived at the scene discovered her lying on the southbound E tracks unconscious and unresponsive, authorities said.

Emergency responders pronounced her dead at the scene, according to police. An investigation remains ongoing, but police said no criminality is suspected.

A preliminary investigation indicates she may have had a medical episode, causing her to faint and fall onto the tracks, according to police.

Police initially said the victim was a 10-year-old girl, but later corrected her age.

Southbound subway service on the E, F and R lines was disrupted after the incident. As of Tuesday afternoon, service along those lines had been restored, according to the MTA's website.