A major US investment firm has agreed to buy a large stake in a Vietnamese conglomerate accused of land grabbing, sexual abuse and destroying indigenous people’s sacred burial grounds in Cambodia.

Global Emerging Markets (GEM), a $3.4 billion “alternative investment group” with headquarters in the heart of New York’s financial district, signed the deal November 6 to buy $80 million worth of Hoanh Anh Gia Lai (HAGL) Group stock, according to HAGL’s website.

The HAGL deal follows a barrage of criticism of the firm over its operations in Cambodia and Laos.

Warren Baker, GEM’s managing director, and other company officials did not respond to requests for comment this week, and calls to GEM’s offices in New York, Paris and Hong Kong went unanswered.

Vo Truong Son, HAGL’s chief financial officer, also did not respond to emailed requests for comment.

A number of investors and former investors, including major European banks, came under fire after investigative group Global Witness released a report last May that detailed HAGL’s alleged abuses.

In February, indigenous communities’ complaints to the World Bank, which invested in HAGL through its International Finance Corporation via a private Vietnam-based investment fund, prompted an internal investigation.

An investigation by the World Bank’s compliance adviser ombudsman detailed allegations that HAGL had depleted fish stocks, encroached on and destroyed sacred land, caused the deaths of hundreds of livestock and two alleged cases of sexual abuse by company employees.

Megan MacInnes of Global Witness on Wednesday said that it was “extremely concerning that a US-based investor with the credibility of GEM would even consider investing in HAGL”.

“HAGL is currently embroiled in an ongoing dispute with indigenous communities in Ratanakkiri [province] whose lives have been devastated by the company and who submitted a formal complaint to the World Bank in February,” MacInnes said.

Last year, Global Witness claimed that HAGL held at least 47,000 hectares of economic land concessions in Cambodia – almost five times the legal limit.

In June, 100 families in Ratanakkiri’s Lumphat district filed another complaint alleging that HAGL had filled in two large lakes which the community depended on.

“While other investors have chosen to divest from HAGL, GEM are doing the opposite. GEM urgently needs to conduct thorough due diligence on HAGL and ultimately reconsider the relationship,” MacInnes said.