The U.S. ambassador is trying to "demonize" Zimbabwe, a state-owned newspaper charged Wednesday, a day after the envoy and other diplomats were detained for an hour at a police roadblock.

U.S. Ambassador James McGee and other diplomats had been investigating allegations of state-sponsored political violence.

The Herald, a government mouthpiece, accused McGee of breaching protocol by leading a fact-finding mission outside Harare. U.S. Embassy officials, though, said the Foreign Ministry had been informed, as required.

McGee "has been on a spirited campaign to demonize the government ahead of the presidential election runoff," the Herald said.

The government has denied reports from opposition officials and human rights groups of government-orchestrated violence meant to undermine support for the opposition before a runoff.

Opposition leader Morgan Tsvangirai claims he won the presidential race outright. But official results released weeks after the poll showed he did not win enough votes to avoid a second round against longtime President Robert Mugabe. No date for a runoff has been set.

Business Day, a respected newspaper in neighboring South Africa, reported Wednesday that another fact-finding team, a panel of retired South African army generals, had found evidence of high levels of state-sponsored violence in Zimbabwe.

South African President Thabo Mbeki, who is trying to mediate between the government and the opposition to end Zimbabwe's political crisis, was briefed on the generals' report during a visit to Zimbabwe last week, Business Day reported.

Mbeki was awaiting the generals' full report before considering how to move "to end any violence that is being perpetrated," South African Deputy Foreign Affairs Minister Aziz Pahad was quoted as saying by the South African Press Association on Wednesday.

While Mbeki has maintained a policy of quiet diplomacy, saying confronting Mugabe could backfire, the United States has been among Mugabe's sharpest critics. McGee has been outspoken, as was his predecessor, Christopher Dell. In 2005, Dell was briefly detained by soldiers while walking in the National Botanical Gardens in Harare, accused of trying to provoke a diplomatic incident by entering a viewing area near Mugabe's official residence.

In Washington on Tuesday, U.S. State Department spokesman Sean McCormack said McGee and the other diplomats with him — from Japan, the EU, the Netherlands and Tanzania — were harassed Tuesday, and that such treatment was indicative of an atmosphere that makes life difficult for citizens who speak out.

At one point at the roadblock, a police officer threatened to beat one of McGee's senior aides. The officer got into his car and lurched toward McGee after he had demanded the officer's name. The car hit McGee's shins, but he was not injured.

McGee climbed onto the hood of the car while his aide snatched the keys from the ignition, then the diplomats used their mobile phone cameras to take photographs of the officer.

McGee insisted the convoy be allowed through and the 11 vehicles carrying diplomats and journalists passed through after about an hour.

Earlier, a priest in northeastern Zimbabwe had led the diplomats to a lumber camp occupied by people described to reporters as ruling party militants. McGee said that, when he confronted them, they hid four notebooks with interrogation schedules.

Lumber yard manager Jim Bennett said at the end of last month at least 100 Mugabe party militants set up a command center on the timber estate about 100 kilometers (60 miles) north of Harare. Bennett said his workers saw police commanders visiting the militant leaders, but no attempts were made to disperse the militants.

"Everybody's scared around here," Bennett said, saying that seven of his workers had been assaulted and many others had been driven into hiding. Others left after timber supplies were stolen by militants, he said.

But Bennett said the violence had only created greater antagonism among his workers toward Mugabe's party.

In the nearby Mvurwi hospital, Kapenda Mwansa, 41, a father of one, said he was attacked by three assailants May 2 who flailed the skin from his back and buttocks with sticks. He was accused of being a "sellout."

A few kilometers (miles) across the bush, staff at the Howard Hospital run by the Salvation Army in the Chiweshe district said they had treated 22 people since May 5 for injuries from beatings to the feet, back, buttocks and legs. At least one was an opposition polling agent, and others were teachers accused of pro-opposition bias when helping run polling stations in the March 29 elections.

Deep cuts showed on Hitler Maguze's wrists from struggling against handcuffs and sores soiled his hospital smock. Maguze said he and his wife were handcuffed, forced to the ground face down and beaten with sticks and chains.

"This is what they do, but it won't make me vote for Mugabe," he said.

One victim died in the hospital from internal hemorrhaging, said nurse Maxwell Manyika. Villagers reported another three people died in the nearby Chaona village after nighttime attacks there.