Source: United Kingdom London Metropolitan Police
Mary, who is also known to her friends and family as Ellen, was last seen leaving her home in Petherton Road, Islington at around 10:30hrs on Monday, 31 March.
She is also known to have links with the Camden area.
Ellen is slim with brown hair. She was last seen wearing a brown jumper, a long dark green skirt and a black hat.
If you have seen Ellen or have any information about her whereabouts, please call 101 and quote the reference 2696/31MAR.