Train services were disrupted for several hours on Monday morning after about a dozen runaway horses escaped from a field onto tracks at Hoo, Kent.
One was electrocuted after straying onto a live line and had to be pulled clear by engineers using a crane.
Buses replaced trains operating between Gravesend and Gillingham until rail services were able to resume.
Bus services were also running from Hastings after a live line caught fire at St Leonards Warrior Square station.
No trains were running between Hastings and Bexhill or from Hastings to Tunbridge Wells because of electrical supply problems.
The line was reopened at about 1300 BST with services expected to resume, but delays still anticipated.
Trains were also running again between Gravesend and Gillingham by lunchtime.