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PHNOM PENH, Cambodia — Forty-three Cambodians arrived in Phnom Penh, Cambodia's capital, on Thursday after being deported from the United States under a law allowing the repatriation of immigrants who have committed felony crimes and have not become U.S. citizens.

The group is the largest to be sent to Cambodia under a 2002 bilateral agreement. More than 500 other Cambodians have already been repatriated.

The program is controversial because it breaks up families, and in some cases the returnees have never lived in Cambodia, having been the children of refugees who fled to camps in Thailand to escape the genocidal Khmer Rouge regime that ruled Cambodia from 1975 to 1979.

Critics of the deportation policy say many of those convicted fell into crime as a result of social dislocation. The returnees are seen as having difficulty reintegrating into Cambodian society because many have spent most of their lives in the United States.

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Two Cambodians ex-convicts on March 30 received pardons from California Gov. Jerry Brown, at least temporarily removing the risk they might be deported.

Gen. Dim Ra, a senior immigration police officer overseeing the returnees, said the group that arrived Thursday included three women.

He said any returnees who still have family members in Cambodia will live with their relatives, and those who do not will receive vocational training by a private group funded by the U.S. government before being integrated into Cambodian society.

The deportation policy has hurt already cool relations between Cambodia and the United States.

Prime Minister Hun Sen said in April last year that he wanted to amend the 2002 pact with Washington that allowed the implementation of the Illegal Immigration Reform and Immigrant Responsibility Act of 1996, meant to combat illegal immigration and terrorism.

Hun Sen, who has led Cambodia for more than three decades, said the agreement should be reviewed on "humanitarian" grounds because it splits up families settled in the United States. Calls to review the act were first raised in 2016 by Cambodian officials, who asked that it be renegotiated or suspended to ease the reintegration problem.

Cambodia then slowed or stopped accepting the return of Cambodian deportees.

In response, the U.S. Embassy in Cambodia stopped issuing visas in September last year to senior Cambodian foreign ministry officials and their families, an action initiated by the U.S. Department of Homeland Security. It said the suspension was implemented under U.S. immigration law in response to Cambodia's refusal to accept back its nationals whom the U.S. wants to repatriate. Similar actions were taken for the same reason against Eritrea, Sierra Leone and Guinea.

Cambodia in retaliation suspended missions by U.S. military-led teams searching for the remains of Americans missing in action from the Vietnam War. The U.S. government lists 48 Americans still unaccounted for in Cambodia.

In February this year, a U.S. State Department official said the visa sanctions on top Cambodian foreign affairs officials could be lifted "in the near future" if the Cambodian government follows through on promises to begin accepting deportees again.

U.S. Assistant Secretary of State for Consular Affairs Carl Risch said during a visit to Cambodia that Cambodian officials had been "very supportive in trying to improve the process."

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