PHNOM PENH, Cambodia (AP) -- A gunman fired a shot early Saturday into one of the main offices of Cambodia's opposition party, a day after the exiled leader of the opposition returned home to an exuberant welcome by supporters ahead of this month's general elections.
The office in the capital Phnom Penh was closed for the night and nobody was injured by the attack. But it was immediately denounced as an effort to intimidate the opposition after the long-awaited return of its leader Sam Rainsy.
"This attack was orchestrated by those in power," said opposition party spokesman, Yim Sovann. He said security guards were sleeping when the shot shattered a window at about 3 a.m.
"They shot at our office to attack our spirit ahead of the election, but this attack doesn't scare us at all," he said.
Police were sent to investigate, said Phnom Penh's police chief, Lt. Gen. Chhun Sovann.
Huge, exuberant crowds turned out Friday to greet Rainsy when he returned home to spearhead his party's election campaign against well-entrenched Prime Minister Hun Sen.
The French-educated leader of the Cambodia National Rescue Party had been in exile since 2009 to avoid serving 11 years in prison on charges many consider politically motivated.
Rainsy, 64, received a royal pardon last week at the request of Hun Sen, his bitter rival whose ruling party is almost certain to maintain its ironclad grip on power in the July 28 general election.
A charismatic and fiery speaker, Rainsy is expected to draw large crowds on a whirlwind schedule taking him to over a dozen provinces in a week.
He started his tour Saturday in Kampong Speu province, 45 kilometers (30 miles) west of the capital.
"I condemn all types of violence," Rainsy said in response to the shooting. "All of us have to respect the law."
The crowd that welcomed Rainsy on Friday was one of the largest ever for a political event in the country, and included well-wishers at the airport, throngs along the route into the city and tens of thousands at the capital's Democracy Square, where he spoke at a campaign rally.
"I have come home to rescue the country," Rainsy told the crowd after arriving at Phnom Penh's airport. Supporters chanted, "We want change!"
Hun Sen has ruled for 28 years, and his party has 90 of the 123 seats in the National Assembly. The 60-year-old prime minister recently said that he intends to stay in office until he is 74 -- cutting back from an earlier vow to stay in control until he's 90.
Rainsy's pardon came after the U.S. and others had said his exclusion from the campaign would call into question the polls' legitimacy. Because he was absent during the registration periods, he will be unable to run as a candidate, or even vote, although his lawyers have said they were seeking a way to allow his participation.
This month's election will be the fifth parliamentary poll since the United Nations brokered a peace deal for Cambodia in 1991, a process meant to end decades of bloodshed that included the communist Khmer Rouge's catastrophic 1975-79 rule, during which an estimated 1.7 million people died in torture centers and labor camps or of starvation or disease.
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