KAMPALA (Reuters) - Uganda said on Thursday it was widening a probe of government officials who allegedly stole aid intended for refugees to include U.N. staff, amid concern the scandal may hold up donor cash needed for the country’s surging refugee population.

FILE PHOTO: A South Sudanese refugee boy looks out of a transit tent at the Imvepi refugee settlement camp in Arua District, northern Uganda, August 22, 2017. REUTERS/Goran Tomasevic/File Photo

Allegations that officials may have inflated refugee numbers to skim aid and engaged in other types of fraud have angered donors and embarrassed a country whose open embrace of a huge influx of refugees from South Sudan’s war has won global praise.

The minister for relief, disaster preparedness and refugees, Hilary Onek, told a news conference: “We are investigating all, including the international community...whether there was connivance together with our staff.”

Asked whether that covered the U.N.’s World Food Programme (WFP) and the U.N.’s refugee agency, known as UNHCR, he said: “All of them are going under scrutiny.”

A UNHCR spokesman in Geneva, Babar Baloch, said the U.N. agency would cooperate with the Ugandan investigation. The UNHCR said last week the probe was initiated after it and WFP brought “grave misconduct by officials” to the attention of authorities.

“UNHCR is encouraged to see Uganda’s resolve to fight fraud and corruption,” Baloch told Reuters on Thursday.

Uganda says it is hosting about 1.4 million refugees, more than a million of them from South Sudan, whose four-year civil war has uprooted a quarter of the country’s population.

Others have flooded in from neighboring Burundi and the Democratic Republic of Congo (DRC).

Violence in the lawless, mineral-rich eastern DRC has reignited recently, and thousands of new refugees are arriving in Uganda daily.

PRAISE, THEN PROBLEMS

Uganda was widely praised for opening its borders, offering refugees a plot of land for cultivation and allowing them free movement and employment rights.

But rising refugee numbers have overwhelmed the available funds, and the WFP had to reduce its food rations last year to cope.

A senior Western diplomatic source in Kampala told Reuters that UNHCR informed donors in Geneva on Jan. 19 of allegations of relief mismanagement. The U.N. then notified the Ugandan government.

Allegations include “large scale sale of food and relief items,” and irregularities in the supply of water, the diplomat said. Onek said the investigations also covered suspected food and cash fraud, bribery and the trafficking of refugee girls. Ugandan government investigators are expected to produce their findings in three weeks’ time.

Five officials in the office of the prime minister, including a senior technocrat, have already been suspended.

Onek said the government, which initially registered refugees itself, has begun checking its numbers using UNHCR’s biometric system and is concerned donors may hold up cash until the allegations are resolved. An aid summit held in Kampala in June drew in pledges of more than half a billion dollars.

Rosa Malango, the U.N. Resident Coordinator in Uganda, said it had begun investigating the allegations. The European Union is also investigating.

U.S. Ambassador to Uganda Deborah Malac told Ugandan officials earlier this month that they must repay any stolen money and prosecute any perpetrators.

But Maria Burnett, a Uganda expert at international rights body Human Rights Watch, said officials had often blocked previous investigations into aid scandals in Uganda.

“A key question now is if senior Ugandan government officials will give prosecutors, investigators, including from Uganda’s anti-corruption institutions, the space to get to the bottom of what happened,” she said.