Searches have been ordered along a busy road in west Belfast after an armoured police vehicle was attacked.
The front windscreen was smashed in the incident on the Glen Road shortly before 1am.
It is understood no explosion was reported at the scene and initial searches in the early hours of the morning did not uncover anything definitive to suggest that an explosive device had been aimed.
Follow-up searches have taken place with a number of roads closed and the area around the incident sealed off.
Detective Sergeant Keith Wilson said there had only been slight damage to a window.
"Police stopped and conducted a search for the object, but were unable to locate anything untoward," he said.
"As a precaution, police are currently conducting a follow-up search in the area and have closed the Glen Road in both directions."
Later, police said nothing was found in searches of the area.
Mr Wilson appealed for witnesses.
"Police inquiries into exactly what kind of object hit the land rover this morning will continue," he said.