PHILADELPHIA (CBS) – A man who worked with abortion doctor Kermit Gosnell at his notorious Women’s Medical Society in West Philadelphia has been sentenced to years in prison.

Fifty-one-year-old Steven Massof was sentenced Wednesday to six to 12 years in prison for killing two viable babies born alive during abortion procedures.

Massof, a medical school graduate without license or certification, worked as a doctor at Women’s Medical Society. He pleaded guilty to Degree Murder, Conspiracy, Corrupt Organizations, and Conspiracy to Commit Corrupt Organization charges in 2011.

Gosnell, who was convicted of killing multiple babies during abortions performed at his clinic, was sentenced to life in prison (see previous story).