About 700 homes are affected by a security alert in a housing estate in Strabane, County Tyrone, after a reported attack on a family home.
It is believed that a device was thrown at a property in Mount Carmel Heights, according to SDLP councillor Jason Barr, who is at the scene.
He said that he understands it smashed a window but did not explode.
In a statement, police said they are “currently in attendance following the discovery of a suspicious object”.
“Motorists are advised to avoid the area and seek alternative main routes for their journey,” officers added.
Speaking to BBC News NI from the scene, Mr Barr said police are waiting for Army bomb disposal officers to examine the object.
He explained there are three large housing estates in the area but there is only one entrance and that road has been cordoned off.
He added that people in the area were facing significant disruption as vehicles cannot enter or leave the estate.
“People on night shifts are worried about how they will get to work,” Mr Barr said.
The councillor described the incident as “another disgraceful act”.
He said residents were being affected for the second time within a year following a two-day alert last November.