Two schoolchildren were treated for minor injuries after a bus collided with a partially fallen tree outside Lisburn on Thursday afternoon.
The bus was travelling along the Glenavy Road with schoolchildren from Forthill College in the upper deck.
It is understood part of the tree hanging over the road crashed through a window in the upper deck following the collision.
Lagan Valley MP Sorcha Eastwood, who went to the scene, said police signs warning of dangers on the road from trees were removed in recent days.
Ms Eastwood added that she believed the bus should not have been travelling along a road that has seen a number of trees fall since Storm Éowyn struck last Friday.
She said that the effects of Storm Éowyn are still being felt, that trees remain in a precarious state and that people should take extra care while out on the roads.
The Glenavy Road was closed between Kilorig Road and School Lane as police and emergency services dealt with the incident.
Two people, both schoolchildren, were treated at the scene, the Northern Ireland Ambulance Service said (NIAS).
“The Northern Ireland Ambulance Service received a 999 call at 16:24 following reports of a traffic incident involving a bus and fallen tree on Glenavy Road,” a spokesperson said.
“NIAS despatched two rapid response paramedics, an advanced paramedic, one ambulance crew and a HART crew to the incident.
“Following assessment and initial treatment at the scene, two patients were discharged with minor injuries. No patients required transport to hospital.”
In a statement, Translink said an Ulsterbus school bus was involved.
“We can confirm an Ulsterbus service (K103) carrying school pupils from Forthill College to Crumlin has been involved in an incident on the Glenavy Road at just after 4pm this afternoon,” the company said in a statement.
“No other vehicles were involved in this incident. Some pupils on the bus were transferred to another bus to continue their journey, while others were collected by parents.
“We have launched an investigation and we are assisting the PSNI with their enquiries.”
Deputy First Minister Emma Little-Pengelly warned people to avoid due to “a double decker bus incident”.
“Looks like it has clipped a overhanging tree. Fire Brigade and PSNI are on the scene. Indications are no serious injuries,” Ms Little-Pengelly, a local MLA, added.
A spokesperson for the PSNI said late on Thursday the road is likely to be closed overnight.
“Please seek an alternative route for your journey. An update will follow in due course.”