Samsung Electronics (Seoul: 005930) said shipments of its latest-version Galaxy S3 smartphone exceed 20 million, only six weeks after passing the 10 million mark. The announcement cements the South Korean electronics giant's lead as the No. 1 seller in the Android OS sector.

The news sent Samsung shares up 7,000 won (US $6.17)in Seoul trading Thursday, closing at 1.196 million won.

The announcement follows Wednesday's debut of three new Android OS phones from Google (Nasdaq: GOOG), the No. 1 search engine, which now owns the Motorola brand as well as rights to Android.

Separately, China Labor Watch, a U.S. group that previously charged Apple (Nasdaq: AAPL) with creating abusive labor conditions at Chinese factories owned by contractors, charged Samsung with similar problems both at its own factories as well as those of contractors. A Samsung representative said the company will investigate them.