Searches have taken place along a busy road in west Belfast after a police Land Rover was attacked.
The front windscreen was cracked in the incident on the Glen Road shortly before 1am on Sunday.
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 took place later in the day 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.
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.