The school run was disrupted for some Northampton parents this morning after a traffic lights malfunction.
Sywell Road near Overstone Primary School was backed up in both directions after two sets of temporary traffic lights were both stuck on red.
The problem was first reported by school staff at 8am but engineers were only able to get traffic flowing about an hour later by using hand-held stop/go signs.
Overstone Primary said a number of children were late as a result.
National Grid started work on road yesterday as part of a scheme to replace gas mains. Work is scheduled to continue for 15 weeks.
A company spokesman apologised to motorists for the inconvenience.