ONCERTED campaign against last Sunday's Son Sann congress extended to road blocksaround Phnom Penh, gagging sections of the media and using heavily-armed militarypolice to clear away hundreds of party followers.The government - which considered the congress illegal - had repeatedly warned thepublic not to attend for fear of violence.The night before the congress, a grenade was thrown at Son Sann's house and anotherat a nearby Wat where supporters of his Buddhist Liberal Democratic Party (BLDP)faction were staying.The government condemned the violence and pledged a full investigation to bring theculprits to justice.Despite the attacks - believed to have injured at least 35 people, including monksand nuns - the Oct 1 congress went ahead.Earlier, some police and military staff attempted to prevent Son Sann supportersfrom traveling to Phnom Penh to attend.The Post witnessed police check points along National Route 2 between Takeo and PhnomPenh, and on another road to Koh Thom district of Kandal, in the early morning ofOct 1.People traveling to the capital were seen to be questioned about why they were goingthere. Those who showed Cambodian People's Party (CPP) or Funcinpec membership cardswere allowed through. BLDP members were not.A policeman in Takmao, who would not be named, said the police had been ordered toenforce a 10pm-5am curfew the night of Sept 30.No-one was to be allowed to travel to Phnom Penh unless they had permission fromMinistry of Interior or National Police officials.Between 5am-9am on Oct 1, the police were told to check the identification of allpeople going to Phnom Penh. There was no formal order to turn back BLDP members,but that was what the police did, he said.BLDP MP and Son Sann supporter Kem Sokha complained that thousands of people hadbeen discouraged or physically prevented from attending the congress.He said he knew of at least five truckloads of supporters turned back by police onRoutes 2 and 3.