* Says has repurchased nearly 4 mln common shares so far

* Shares rise in morning trading on NYSE, TSX (Adds background, analyst's comment; updates share price move)

By Euan Rocha

TORONTO, Sept 15 (Reuters) - Embattled miner Silvercorp <SVM.TO>, caught in a maelstrom of anonymous fraud allegations, said on Thursday its shares are undervalued and it is pushing ahead with its share repurchase plan.

Silvercorp, which has shed more than $1.5 billion in market value in the last five months, said it has bought nearly 4 million of its outstanding shares since June 17, when its board authorized a buyback of up to 10 million shares.

The company said it is purchasing its own shares because the market is undervaluing them relative to the value of its assets. It has spent a total of C$31.3 million, or C$7.97 a share on average, in the buy-back program so far.

The Vancouver-based company, which operates silver mines in China, is the latest China-focused and North American-listed company to fall into the cross-hairs of short-sellers who have published scathing fraud allegations.

Silvercorp denies the allegations, which are similar to those that felled Sino-Forest <TRE.TO>, which not long ago was the largest Canadian-listed forestry company. Sino-Forest and many other China-focused companies are now at the center of regulatory investigations and lawsuits.

Silvercorp, which operates silver mines in China, on Wednesday issued a raft of figures on its tax payments, assay results and other details that it contends disprove all the short-seller allegations against it. Chief Executive Rui Feng dismissed the allegations of fraud, and accused short-sellers of using a "short and distort" scheme.

"We need new regulations to go after these people, who short a company and then put out a false statement," Feng said in an interview with Reuters.

BMO analyst Andrew Kaip commended the company's rebuttal of the allegations and reiterated BMO's "outperform" rating on its shares, but noted that the share price is likely to remain volatile for now.

"BMO Research views the company's proactive approach toward disclosure to repudiate the short-seller's allegations as a positive step," Kaip said in a note to clients.

Shares of the company rose 4 percent to C$6.69 in morning trading on the Toronto Stock Exchange on Thursday, while its New York-listed shares were up 5 percent at $6.81.

($1=$0.99 Canadian) (Reporting by Euan Rocha; editing by Janet Guttsman and Peter Galloway)