SEOUL - Samsung came under renewed criticism from a rights group on Tuesday for illegal work practices at its Chinese suppliers, a day after the South Korean electronics giant admitted excessive overtime and fines for employees in China.

A number of foreign companies have been accused in recent years of improper labor practices in China, seen as a cheap source of labor for their production lines.

New York-based China Labor Watch said employees at one of Samsung's suppliers sometimes worked up to 16 hours a day, with only one day's rest a month.

Samsung Electronics Co said on Monday a review of 105 of its Chinese suppliers - involving more than 65,000 employees - found illegal work practices, but said the companies involved would be given two more years to change their ways.

Samsung said the audit had found no evidence of child labor.

The company said in a statement that it has identified the need for initiatives to reduce employee overtime as a top priority, and is researching and developing measures that will eliminate hours beyond legal limits by the end of 2014.