The 74-year-old Union woman who went missing last week has been found at a New York City hospital, authorities said Monday.

Mary Ann Clark is in serious but stable condition at Mt. Sinai Hospital on Madison Avenue in Manhattan after suffering a medical episode on a subway Friday morning while on her way to work, Union police said.

Clark was on a No. 1 subway approaching the 14th Street station when she fell ill. Two passengers came to her aid and stayed with Clark until paramedics arrived, Union police said.

Clark was brought to Mount Sinai Beth Israel and later transferred to the hospital's Madison Avenue location.

Police learned of her whereabouts Monday morning after receiving a call from Vincent DiTomasso, one of the people who aided her. Police then confirmed she was still hospitalized after speaking with family members who arrived in New York to see her.

"We want to give credit to the caller who aided her," a Union police spokesman said of DiTomasso, a member of an electrical union who was on his way to work Friday morning. "He cared for this total stranger and did right by her."

Clark is awake and alert, but not yet able to speak, police said.

Jeff Goldman may be reached at jeff_goldman@njadvancemedia.com. Follow him on Twitter @JeffSGoldman. Find NJ.com on Facebook.