Russ Wiles

The Arizona Department of Revenue said it stopped more than $74 million in fraudulent income-tax refunds from being sent out over its most recent fiscal year — an amount more than double that of the prior 12 months, attesting to the increased seriousness of the issue.

The department acknowledged that tax fraud has become a big problem, with people filing false returns using stolen or fictitious taxpayer information to receive refunds. In fiscal 2012-13, $32 million in fraudulent refunds were halted.

“To give an idea of how dire this problem has become, consider that just five years ago we stopped less than $2 million in fraudulent refunds,” said Anthony Forschino, an assistant director in charge of criminal investigations.

The problem also is causing headaches for the Internal Revenue Service and tax agencies in other states. Earlier this year, the IRS said it stopped 14.6 million suspicious returns seeking $50 billion in false claims from 2011 through November 2013.

It also has more than 3,000 employees focused on this effort. Still, the IRS pays out at least $5 billion a year in fake returns, according to a Treasury Department estimate.

Tax fraud adds to government fiscal pressures and creates tax-filing complexities, including delayed refunds, for innocent taxpayers who become victims.

The IRS has said it is stepping up enforcement, with criminal probes rising 66 percent, to 1,492 cases in fiscal 2013. Those convicted have received prison terms averaging 38 months. The Arizona Department of Revenue did not provide comparable data.

Forschino said the Arizona Department of Revenue has enhanced its computer-based scrutiny of returns and has assigned highly trained auditors and investigators to tackle the tax-fraud problem. The department also is working with the IRS, other states and lawenforcement agencies to share information.

NEW YORK — More travelers are flying than ever before, creating a daunting challenge for airlines: keeping passengers safe in an ever more crowded airspace.

Each day, 8.3 million people around the globe — roughly the population of New York City — step aboard an airplane. They almost always land safely.

Some flights, however, are safer than others.

The accident rate in Africa, for instance, is nearly five times that of the worldwide average, according to the International Civil Aviation Organization, part of the United Nations. Such trouble spots also happen to be where air travel is growing the fastest, putting the number of fliers on course to double within the next 15 years.

“In some areas of the world, there’s going to be a learning curve,” said Patrick Smith, a commercial-airline pilot for 24 years and author of “Cockpit Confiden-