A major clean up is underway after torrential rain forced the closure of Magherafelt's Meadowlane shopping centre.
At least nine businesses were flooded at the Moneymore Road end of the centre around 7pm.
It is understood an underground car park became flooded before water poured through the doors into the shopping mall.
"Shoppers had to run out of the way of the water," said an eye witness. "It was crazy. The whole thing happened so quickly."
The centre was evacuated and NI Fire and Rescue crews managed to bring the flooding under control.
Sandbags were being placed at the entrance to prevent flood water running from Rainey Street park into the undergrouknd car park.
Business owners have started cleaning up and counting the cost.
Several expressed the hope that they would be able to open for business in the morning.
SDLP Mid Ulster Assembly member Patsy McGlone, who was at the scene, said it was "shocking" and expressed sympathy with all those affected. The Met Office has a Yellow warning in place for heavy rain.