The Netherlands Food and Consumer Product Safety Authority (NVWA) declared on Thursday that they found antibiotic residues in two samples of beef contaminated with horsemeat.

The NVWA has started a major research into the mixing of horsemeat in beef in the Netherlands since horsemeat scandal spread across Europe, the NVWA spokesman Tjitte Mastenbroek told Xinhua.

In the latest case, they revealed antibiotics in one of two loads of contaminated meat and the meat was immediately seized, according to the NVWA.

"One of the two loads exceeded the maximum allowable limit for antibiotic residues and the other does not," said Mastenbroek. "Both loads of meat were from Poland."

The NVWA investigated over 160 companies, collecting a total of 500 samples of meat scraps, meat and foodstuffs so far.