RIO DE JANEIRO (REUTERS) - Tomasz Zielinski, brother of the 2012 Olympic champion Adrian Zielinski, has become the second weightlifter sent home from the Rio Games for doping.

European champion Zielinski, due to compete with his brother in the 94kg, tested positive for nandrolone. On the day of the opening ceremony, Cyprus announced that they had sent home Antonis Martasidis, an 85kg lifter, when an out-of-competition test came up positive.

Szymon Koecki, head of the Polish weightlifting federation, said: "I want to sincerely apologise to all Poles that during the Olympic Games they have to feel ashamed as the whole world looks on."

Koecki was a silver medallist at Sydney 2000 and Beijing 2008, and is expected to be upgraded to gold in the latter because of the retrospective positive test of champion Ilya Ilyin, of Kazakhstan. Koecki missed the 2004 Games because of a two-year doping ban.

Tomasz Zielinski is the fifth Polish weightlifter to have tested positive since 2012.