Gold Coast - A spectator dropped a mobile phone onto the cycling track during the first session at the Commonwealth Games on Thursday, drawing warnings of a "major accident".

The incident took place during the men's team pursuit as racers pelted round the banked track in Brisbane.

The riders were unhurt but it drew a curt warning from the stadium announcer to the packed crowd at the Anna Meares Velodrome in Brisbane.

"Please be careful, a mobile phone has just been dropped onto the track," said the announcer, warning of the potential of a "major accident" if it had come into contact with one of the riders.

Spectators in the front row at the velodrome are right on top of the action on the track, which slopes down at a steep angle.