Army bomb experts have been called out to deal with a suspicious object that was discovered on the Drum Road Between Cookstown and Omagh.
Police and army are believed to have arrived at the scene - thought to be in the Creggan area - at around 11pm last night, with the situation continuing on Easter Monday morning.
Road closures are in place at the junction of Barony Road and Sultan Road, and also Barony Road and Loughdoo Road.
Diversions are in place.
Tyrone footballer, Gemma Begley tweeted about the incident late on Easter Sunday.