Move seen by rights groups as a bid to undermine democracy and to entrench the PMs power before this months polls.
The son of Cambodias long-serving leader was promoted to two senior military posts on Saturday as his father looks to tighten his familys grip on the countrys leadership.
The move comes after 12 generals were accused of committing decades ofhuman rightsabuses to prop up Prime Minister Hun Sen in aHuman Rights Watchreport released on Thursday.
Hun Sen is alleged to be priming his three sons for a political dynasty in advance of national elections he is expected to win this month after thedissolutionof the main opposition party last year.
His eldest son, Lieutenant General Hun Manet, was promoted to acting chief of joint staff and commander of the army headquarters, according to defence ministry spokesperson Chhum Socheat.
The 40-year-old West Point-trained officer will keep his current roles as head of the defence ministrys anti-terrorism unit and the deputy commander of Hun Sens personal bodyguard unit.
The defence spokesperson said Hun Manets promotion was merit-based and not because of his family name.
There is nothing strange, his promotions have been made based on his qualifications and experience in the army, Chhum Socheat told AFP news agency on Saturday.
Hun Sens second son, Hun Manit, is the head of a powerful military intelligence unit and his youngest, Hun Many, is a parliamentarian who oversees the ruling partys far-reaching youth movement.
Two generals named in the Human Rights Watch report – Pol Saroeun and Kun Kim – also stepped down from their senior military roles this week in order to run for parliament in the July 29 vote.
These 12 men are the backbone of an abusive and authoritarian political regime over which an increasingly dictatorial Hun Sen rules, the report said of the generals.
They were accused of violations of human rights, war crimes, and crimes against humanity committed from the 1970s to the present, it said.
Most of the 12 have been implicated in the use of unnecessary, excessive, and sometimes lethal force against protests about unfree and unfair elections, land confiscations, labour abuses, and low wages.
The Cambodian defence ministry denied the HRWs allegations, calling it a deranged report.
Several others were moved in the military shuffle, including military police commander-in-chief Sao Sokha who was appointed acting supreme commander of the Royal Cambodian Armed Forces.
One of the worlds longest-serving leaders, Hun Sen is accused of stifling political freedoms in the country.
The previous largest opposition party, the Cambodia National Rescue Party (CNRP) was dissolved in November after being accused of plotting to overthrow the government.
They performed well in the last general and in local elections, but candidates lost their seats when the party was banned.
The opposition leader Kem Sokha was jailed andcharged with treason.
There has been international condemnation of the move with 45 countries signing a letter calling for the opposition to be reinstated and for Kim Sokha to be freed.
TheUnited Statesand theEuropean Unionhave also withdrawn funding for Julys vote.
The government says it is not concerned about the criticism, and will not intervene in the judicial process.
They can voice, but that doesnt reflect the spirit of all the people in those countries. Theyre very negative on Cambodia today, but in the future, they will come back to us, its normal, Huy Vannak from the Cambodian interior ministry told Al Jazeera.
Many locals, however, arelosing faithin the political process.
Most people who used to support my party in the area say that if theres no Cambodia National Rescue Party in the election, they wont vote, CNRP candidate Hean Keu said.
Several independent media outlets have been shut down inCambodiaduring the past year.
In September, independent newspaper The Cambodia Daily announced it was shutting down after being slapped with a $6.3m tax bill, which its publishers said was politically motivated.
The Dailys closure came weeks after a government crackdown on 32 radio stations, including Radio Free Asias Phnom Penh bureau, according to figures compiled by Reporters Without Borders (RSF), an organisation aimed at protectingpress freedom.
RSF alleges Hun Sens government is leading an all-out war on independent media outlets with the aim of ensuring victory in the general elections.
Several senior staff at the Phnom Penh Post alsoresignedin May, after the publications new owner fired the editor-in-chief over a story concerning the papers sale to Malaysian businessman Sivakumar S Ganapathy.
Under the headline Phnom Penh Post sold to Malaysian investor, the article raised concerns over Ganapathys links to Hun Sen and the Malaysian government.
We are worried about our editorial independence heading into this years national elections Cambodia has lost a lot of independent media, so we were widely considered to be the last independent news outlet here, Post reporter Erin Handley told Al Jazeera.
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