Transport group Stagecoach yesterday said an excellent performance from its rail arm - including increased passenger numbers on the improved West Coast Mainline - had helped it notch up a 13 per cent rise in profits.
However, the group was criticised for "minting it at the public's expense" by a transport trade union.
Bob Crow, general secretary of the Rail, Maritime and Transport Union, claimed Stagecoach shareholders were profiting from taxpayer handouts to the railways.
Mr Crow said private companies had cost the railways more than £6 billion since privatisation and it was time they were brought back into public ownership.
Stagecoach said its rail division's profits had risen
10.2 per cent to £48.6 million, helping it to lift pre-tax profits in the year to April 30 to £ 108 . 3 million from £95.8 million a year ago.
It runs South West Trains, Island Line on the Isle of Wight and has a 49 per cent stake in the Virgin Rail Group, which runs the West Coast and CrossCountry franchises.
Stagecoach said the improved profits were due to the introduction of new trains and a revamped timetable that had helped to improve punctuality and reliability.
However, Mr Crow said: "It is no wonder their profits are soaring because they get three times the subsidy British Rail used to receive, so it is like winning the National Lottery every day.
"South West Trains bagged £92 million in public subsidy in 2003-04 and the two Virgin operations which Stagecoach owns half of, was given more than half a billion.
"When it comes to the next pay round, our members will no doubt remember that Stagecoach's shareholders are set to receive a 15 per cent dividend rise."
However, chief executive Brian Souter said Stagecoach had achieved the strong results despite significant cost pressures in the transport industry, particularly for fuel.
He added that the group, which is bidding to run the new Greater Western, Thameslink and Integrated Kent rail contracts, was well placed to benefit from new franchising opportunities.
"I am confident our cashgenerative portfolio will produce further significant growth," he said.
The group also has a 49 per cent stake in Virgin Rail Group, which comprises the Virgin West Coast and Virgin CrossCountry franchises, and runs on the basis of budgets set by the Strategic Rail Authority.
Despite teething troubles, including breakdowns and faulty toilets, Stagecoach said passenger volumes on Virgin's West Coast main line franchise had risen about 20 per cent since September 18 after the introduction of new tilting Pendolino trains.
The group also said it expected further passenger growth if progress in infrastructure improvements by Network Rail accompanied the lower journey times and higher frequencies brought about by the new trains.
Stagecoach said passenger volumes at South West Trains rose by 4.8 per cent against the year before while operating profits lifted 10.2 per cent to £48.6 million.
It also said train punctuality had increased, with more than 90 per cent of trains now arriving on time.
The group was the first among south-of-London operators to complete the replacement of its old slam-door rolling stock with a £1 billion fleet of new Siemens Desiro trains.
The company also runs about 7,000 buses in nearly 100 towns and cities in the UK.
It said its UK bus division had also had an excellent year, increasing turnover by 10.8 per cent to £720.3 million and operating profits by 10.3 per cent to £82.5 million.