Police arrested 36 people and accused them of attempting to violently enforce a nationwide strike called by Zimbabwe's opposition to press for the release of presidential election results, authorities said Wednesday.

A judge, meanwhile, acquitted New York Times correspondent Barry Bearak and British journalist Stephen Bevan of covering the election illegally. Their lawyer said they were now free to leave the country.

Magistrate Gloria Takwunda said the state "failed dismally to prove that there was reasonable suspicion of them practicing as journalists." She said state evidence was "inconsistent and unreliable."

The two men were held by police for days following their arrest on April 3. They have been free on bail for more than a week but blocked from leaving the country pending the court ruling.

"My clients are free to go, they are no longer on remand," lawyer Beatrice Mtetwa said. The New York Times reported on its Web site Wednesday that Bearak had left the country.

Zimbabwe has waited 18 days for results from its presidential vote. The electoral commission says it is verifying votes and investigating anomalies, but the opposition says longtime ruler Robert Mugabe is using the delay to secure his 28-year grip on power.

Opposition leader Morgan Tsvangirai says he won the March 29 election outright. Independent tallies show Tsvangirai won, but not by enough to prevent a runoff.

Failing to persuade courts to force the release of the results, the opposition called for Zimbabweans to stay away from their jobs starting Tuesday in a show of solidarity, but there were few indications that many people heeded the call.

Although there were some street barricades and fewer commuter buses running than normal, most stores and banks opened and downtown was bustling.

Police arrested 36 young suspects in Harare and four other cities for blocking streets, stoning cars and buses and preventing people from going to work, said police spokesman Wayne Bvudzijena.

The police presence remained heavy Wednesday, with soldiers carrying assault rifles and police in riot gear stationed across Harare and its suburbs.

A freelance cameraman also was arrested Tuesday while filming in Harare, according to an Associated Press journalist who saw the incident. The government refused accreditation to many foreign reporters and a number have been detained for covering the vote without permission.

The opposition, human rights groups and diplomats have accused the police and ruling party militants of targeting perceived Mugabe opponents since the election. Zimbabwe Doctors for Human Rights said it treated 174 cases of injuries consistent with assault and torture since the vote, including 17 on Wednesday. Most of the new cases were multiple fractures, the group said.

In New York, U.N. Secretary-General Ban Ki-moon said he was deeply concerned about the failure to release the election results.

"Absent a transparent solution to this impasse, the situation could deteriorate further with serious implications for the people of Zimbabwe," he warned. "The credibility of the democratic process in Africa could be at stake here."

British Prime Minister Gordon Brown, who also attended the high-level U.N. Security Council meeting on African peace and security issues, said "No one thinks, having seen the results at polling stations, that President Mugabe has won this election."