At least 20 people were injured on Monday when two cranes collapsed on buildings while restoring a bridge in central Dutch town of Alphen aan den Rijn.

"Two cranes and the stretch of roadway they were carrying fell on five houses in all. There are about 20 injured," fire fighter bridgade spokesperson Ton Koot said, according to DW.

The accident happened at the Juliana Bridge, which is undergoing a major restoration. Amateur video showed one crane trying to lift the main deck section of the bridge and collapsing under the weight, pulling the second crane and the section of bride deck with it, according to BBC.

"You see the cloud of dust rise - that is a terrible image and you think, 'Who is under there?' You can't believe what you see," an eyewitness told national broadcaster NOS, according to DW.

The piece of bridge and the cranes hit several buildings including a shop selling second hand goods and a shop selling artists supplies, according to Dutch News.

The rescue team brought in to search for people in debris as it remained unclear how many people were in the shop when the crane collapsed.

"It is not clear how many people were trapped under the rubble. The victims have the highest priority," deputy mayor of town Kees van Velzen said at a press conference, according to NLTimes.

See the dramatic video of collapse here