SACRAMENTO (CBS/AP) – The nation’s largest teachers’ pension fund says it will review its holdings after being criticized for having an investment in the manufacturer of an assault rifle used in last week’s Connecticut school massacre.

California State Teachers’ Retirement System spokesman Michael Sicilia said Tuesday that the $155 billion pension system is making sure its investments comply with the fund’s own social and ethical standards.

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The fund invested $600 million in the private equity firm Cerberus Capital Management, which owns gun maker Freedom Group International. Cerberus said it will sell its holdings in the manufacturer of the rifle used to kill 20 schoolchildren and six adults at a school in Newtown, Conn.

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State Treasurer Bill Lockyer has asked CalSTRS and the state employees’ pension fund to reconsider any investments in firearm manufacturers.

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