UPDATE 2.29pm
Normal train services have resumed on the Pakenham line after a fallen tree was cleared from the tracks.
The tree, which had fallen shortly after noon, was cleared by 2pm.
EARLIER 1pm
A fallen tree across a rail track near Hallam has put a halt to rail services on the Pakenham line.
About 12.30 today (17 July) Metro Trains announced that buses would replace trains between Dandenong and Berwick, but would take about an hour to arrive.
It advised commuters to use local bus services in the meantime, which would add an extra 20 minutes to travel times.
Metro Trains tweeted that it was confident that the track would be cleared ahead of the afternoon peak.
