Anworth Mortgage Asset Corp. said Monday that it plans to make a public offering of 9 million shares of common stock in an effort to acquire more capital to buy mortgage securities.

The Santa Monica-based real estate investment trust said it plans to net slightly less than $61 million from the sale, which it will use to buy traditional, prime mortgages on the secondary market that fit Fannie Mae and Freddie Mac guidelines, the company said.

Anworth added that it may issue up to 1.35 million additional shares to cover over-allotments.

Shares in Anworth lost 6 percent to $6.68 in early trading Monday on the New York Stock Exchange.