Police and fire crews attended a mains gas leak in the Marsh Barton area of Exeter on Thursday evening.
Reports of the incident emerged at around six o' clock after the closure of Bad Homburg Way in Matford, with police officers evacuating offices and closing roads in the 250 metre exclusion zone in the following 40 minutes.
Gas engineers were called, repairing the damage with four fire crews standing by as a precaution.
Roads in the area have now reopened.