Tyson Foods is expanding the recall of its chicken strips, after getting more complaints that buyers found pieces of metal in their dinners, federal officials said.

The recall began in March, when the company said 69,000 pounds of its frozen chicken strips would be taken off the shelves.

The new recall brings the number to 11.8 million pounds.

Six people claimed to have found metal in their chicken and three said they suffered mouth injuries, CNN reported.

The recalled products have the code P-7221 on the back of the packages.