Japanese retail sales grew at the strongest pace in 5½ years in September as consumers rushed to buy big-ticket items to beat a rise in the country's sales tax, raising concerns spending could pull back sharply in the coming months.

The Oct. 1 increase in the consumption tax from 8 percent to 10 percent is seen as crucial for fixing the industrial world's heaviest public debt at more than twice the size of Japan's economy.

But some analysts worry the twice-delayed tax hike could tip the world's third-largest economy into recession, underscoring the challenge for the Bank of Japan to sustain growth and accelerate inflation toward its 2 percent target.