Tokyo stocks opened slightly lower in early trading Friday as the yen's firmer and concerns over Greece' s bailout referendum dented market sentiment.

At 9:15 a.m., the 225-issue Nikkei Stock Average was down 60.62 points, or 0.30 percent, from Thursday to 20,461.88.

The broader Topix index of all First Section issues on the Tokyo Stock Exchange gained 0.96 point, or 0.06 percent, to 1,649. 20. The Topix opened higher before zigzagging between positive and negative territory.

Decliners were led by mining, insurance and retail issues.