A concrete girder or `section’ of an under-construction metro bridge developed a crack soon after it was launched on pillars here on Tuesday, officials said.

While traffic was diverted as a precautionary measure, the “deformed” concrete segment, part of a span having nearly a dozen such box girders, will be replaced, they said.

The span between pillars 747 and 748 is part of the east-west corridor of the metro project connecting Saroli with Kapodra, said a release by the Gujarat Metro Rail Corporation Ltd (GMRC).

“The final stressing of the box girder span was completed at 1:30 am and it was kept under observation for 24 hours as per rules. At around 2:00 pm, one segment deformation was noticed. The deformation of the bridge is being continuously monitored and is in stable condition,” said the statement.