A police helicopter has captured the moment a man walking his dog on a Gold Coast footbridge used a clothesline tackle on a sprinting car thief and held him down until officers caught up.

As police cuffed the alleged criminal, the dog-walker picked up the thong he lost during the scuffle and walked away, giving another police officer a high-five as he passed by.

The alleged car thief, a 40-year-old man, was charged with a string of serious driving offences.

Police are appealing for the Good Samaritan to come forward so he can be thanked.