Apple Inc. shares fell the most in two years after posting the slowest profit growth since 2003 and weakest sales increase in 14 quarters, Bloomberg reported.

The shares dropped 9.7 percent this morning, the biggest intraday decline since May 2010.

Fiscal first-quarter profit rose less than 1 percent to $13.1 billion, or $13.81 per share. Sales rose 18 percent to $54.5 billion, compared with 73 percent growth in the same period a year ago.

Yesterday's results reported by Apple underscored the rising costs of product overhauls amid competition from Samsung Electronics Co. in the saturating smartphone market. 

Apple had record revenue from iPad and iPhone sales, but investors worry about management's ability to keep producing hit products more than a year after the death of co-founder Steve Jobs.