Stranraer recovered from being a goal down at half time to beat Peterhead 2-1 thanks to goals from Willie Gibson and Jamie Longworth.
Morton had to wait until the 45th minute of their game with Dunfermline Athletic to take the lead through Stefan McCluskey, but were dominant in the second half as goals from Lee Kilday, Declan McManus and Mark Russell completed the rout.
Forfar, meanwhile, were in control from start to finish as goals from Dale Hilson, Omar Kader, Chris Templeman and a Chris Smith own goal gave them a comfortable win against Stirling Albion, who remain anchored to the bottom of the table.
Elsewhere, Ayr United moved level on points with Stenhousemuir, who were beaten 2-1 by Airdrieonians thanks to a brace from Bryan Prunty, as a goal from Brian Gilmour and a Jon-Paul McGovern penalty earned them a 2-2 draw with Brechin City.
Results in full: Airdrieonians 2-1 Stenhousemuir, Ayr United 2-2 Brechin City, Dunfermline Athletic 0-4 Greenock Morton, Forfar Athletic 4-0 Stirling Albion, Peterhead 1-2 Stranraer.