A PSNI spokesperson said: “The 55-year-old was last seen in the Glenburn Park area of Magherafelt on Monday, June 3.
“However, unconfirmed sightings have also placed him in Rainey Street in the town on Tuesday, June 4.
“He is described as being approximately 5’ 4”, of stocky build with short or shaven black hair, and he has brown eyes.
“It’s understood Stephen was last seen wearing jeans, dark trainers and a dark top or a bomber-type style jacket.
“If you have any information in relation to his whereabouts or you believe you may have seen him, please contact police on 101, quoting reference number 1603 08/06/24.
“Police would also ask local residents and property owners to check their outbuildings and sheds, and local business owners to check their CCTV footage.”